ask him nicely
suspicious play

You can get one game analysised by computer a month (something like that). If someone plays like a beginner and then all of a sudden starts to find all the best moves then - shizam you may be on to something.
However, the whole cheater finger pointing thing is a nasty business so you'd have to be super sure before doing anything. You could also ask for help from the staff here, I guess.

The Report Abuse link is at the bottom of the page. Use it if you are certain. If not certain, maybe ask a higher ranked player you trust for their opinion first. I've reported three players and two were banned. I never played them; they were in tournamanets I joined.
I see nothing suspicious in your last ten games.

Erik wrote: How do I report someone I think is cheating?
If you are suspicious about somebody cheating, please use the Report Abuse link and include all relevant information. We investigate all reports.
http://www.chess.com/forum/view/community/cheating-at-chess-on-chesscom---questions-and-answers

Should the information on reporting suspected cheating be even easier to find/access?
It is true that Erik's post Cheating at Chess on Chess.com - Questions and Answers is PINNED at the top of the list of Unanswered Posts.
It is also true that the Report Abuse link is at the bottom of EVERY chess.com page. However, as was pointed out here ... http://www.chess.com/forum/view/community/chesscom-feature-request-and-wishlist-4?page=16 ...
Very few people are aware of [THESE LINKS] until they are pointed out by someone else. There is seldom a need to scroll to the bottom of the screen. Would it be a good idea to provide a copy of these bottom-of-page links as a dropdown menu to a new command toolbar item EXTRAS at the TOP of every page - alongside PLAY LEARN READ etc. ?
Also, not everyone immediately associates suspected cheating with abuse. So a Report Suspected Cheating link might be something to consider.
If you suspect your opponent has not exactly played fairly, is there anyway of finding out?
Since I'm nosey, I checked your games and saw that you lost to someone 500 points lower then you..
Is this the game you're referring to?
You didn't play that well.. I don't think getting beat equals suspicious play.

i once got beat by an opponent rated 1000, he won all of his games in that tournament, i thought it suspicious, so i called the CGMEBUS ("chess grand masters elite beat up squade" obviously) and got secret agent Victor Korchnoi to play chess boxing against him, today he is in a special institution, he can never walk again and keeps talking about chessclocks ticking in his head all the time, his doctors are considering Euthanasia.

A guy rated 300 points lower than I am beat me four of four in a tournament. And in tournaments I focus more than I do in other games. No doubt he either cheated against me or held back in his other games, presumably to qualify for tournaments with a rating limit. I never filed a formal complaint first because I don't care that much (this guy seems to have bigger issues than his chess rating or any ego derived therefrom), and second, how can one really prove it anyway? I have had opponents have their accounts closed for cheating (never at my initiation), and I have always wondered how this determination can be made. Or made reliably. Is it not said that a chimp with enough time and patience will eventually type all of Shakespeare's sonnets? Great play may be:
1) cheating;
2) brilliance on the part of a strong player, maybe recently made strong;
3) luck.
But luck is not cheating. Who knows? Any one of us could blindly stumble onto a set of moves that would turn out to be the elusive holy grail winning strategy!

Is it not said that a chimp with enough time and patience will eventually type all of Shakespeare's sonnets?
It is said, but it is not correct.
The fact is, the monkeys tend to press the same key over and over: http://news.bbc.co.uk/1/3013959.stm
Edit - This quote was too funny to leave out:
- A single computer was placed in a monkey enclosure at Paignton Zoo to monitor the literary output of six primates. But after a month, the Sulawesi crested macaques had only succeeded in partially destroying the machine, using it as a lavatory, and mostly typing the letter "s".
Also, mathematically speaking, the odds of a monkey correctly typing even the first 20 letters (not accounting for spaces, capitalization, and punctuiation) of any sonnet is 1 in 19,928,148,895,209,409,152,340,197,376 (yes, that's the real number). So, again speaking mathematically and not taking into account the propensity for a monkey to repeat keys, given the theoretical age of the universe, a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant.
The only thing that can be said is "it might be possible" given the limited human capacity for understanding things so large.
Perhaps it is better to go with the Buddhist method - accept that we can not know (and stop saying it!).

Is it not said that a chimp with enough time and patience will eventually type all of Shakespeare's sonnets?
It is said, but it is not correct.
The fact is, the monkeys tend to press the same key over and over: http://news.bbc.co.uk/1/3013959.stm
Edit - This quote was too funny to leave out:
A single computer was placed in a monkey enclosure at Paignton Zoo to monitor the literary output of six primates. But after a month, the Sulawesi crested macaques had only succeeded in partially destroying the machine, using it as a lavatory, and mostly typing the letter "s".Also, mathematically speaking, the odds of a monkey correctly typing even the first 20 letters (not accounting for spaces, capitalization, and punctuiation) of any sonnet is 1 in 19,928,148,895,209,409,152,340,197,376 (yes, that's the real number). So, again speaking mathematically and not taking into account the propensity for a monkey to repeat keys, given the theoretical age of the universe, a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant.
The only thing that can be said is "it might be possible" given the limited human capacity for understanding things so large.
Perhaps it is better to go with the Buddhist method - accept that we can not know (and stop saying it!).
Incorrect Neospooky.
The key to the original statement, "given enough time" makes the age of the universe insignificant. In fact, since "given enough time" can be any amount of time between zero units and unfinity, the probability of the monkeys typing anything that is suggested (i.e. sonnets, bibles, novels, etc.) is effectively one (or 100% if you do not have a background in probability).
This is, of course, assuming the pressing of keys is essentially random, and "not taking into account the propensity for a monkey to repeat keys" as you did.
The bottom line is very large numbers (or very small probabilities) are not really relevant when given an infinite amount of time.
The conclusion, therefore, is that the statement that "a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant" is an incorrect statement when the proper parameters are instituted.

Is it not said that a chimp with enough time and patience will eventually type all of Shakespeare's sonnets?
It is said, but it is not correct.
The fact is, the monkeys tend to press the same key over and over: http://news.bbc.co.uk/1/3013959.stm
Edit - This quote was too funny to leave out:
A single computer was placed in a monkey enclosure at Paignton Zoo to monitor the literary output of six primates. But after a month, the Sulawesi crested macaques had only succeeded in partially destroying the machine, using it as a lavatory, and mostly typing the letter "s".Also, mathematically speaking, the odds of a monkey correctly typing even the first 20 letters (not accounting for spaces, capitalization, and punctuiation) of any sonnet is 1 in 19,928,148,895,209,409,152,340,197,376 (yes, that's the real number). So, again speaking mathematically and not taking into account the propensity for a monkey to repeat keys, given the theoretical age of the universe, a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant.
The only thing that can be said is "it might be possible" given the limited human capacity for understanding things so large.
Perhaps it is better to go with the Buddhist method - accept that we can not know (and stop saying it!).
Incorrect Neospooky.
The key to the original statement, "given enough time" makes the age of the universe insignificant. In fact, since "given enough time" can be any amount of time between zero units and unfinity, the probability of the monkeys typing anything that is suggested (i.e. sonnets, bibles, novels, etc.) is effectively one (or 100% if you do not have a background in probability).
This is, of course, assuming the pressing of keys is essentially random, and "not taking into account the propensity for a monkey to repeat keys" as you did.
The bottom line is very large numbers (or very small probabilities) are not really relevant when given an infinite amount of time.
The conclusion, therefore, is that the statement that "a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant" is an incorrect statement when the proper parameters are instituted.
Thanks StatsMan! I guess we statisticians see things the same way ... well, at least issues relating to laws of large numbers! But in all seriousness, suppose that by chance and luck alone I happened to stumble onto something brilliant, and defeat a much stronger player, totally out of character with my other games. For this I get banned? McCarthy is alive and well?

Is it not said that a chimp with enough time and patience will eventually type all of Shakespeare's sonnets?
It is said, but it is not correct.
The fact is, the monkeys tend to press the same key over and over: http://news.bbc.co.uk/1/3013959.stm
Edit - This quote was too funny to leave out:
A single computer was placed in a monkey enclosure at Paignton Zoo to monitor the literary output of six primates. But after a month, the Sulawesi crested macaques had only succeeded in partially destroying the machine, using it as a lavatory, and mostly typing the letter "s".Also, mathematically speaking, the odds of a monkey correctly typing even the first 20 letters (not accounting for spaces, capitalization, and punctuiation) of any sonnet is 1 in 19,928,148,895,209,409,152,340,197,376 (yes, that's the real number). So, again speaking mathematically and not taking into account the propensity for a monkey to repeat keys, given the theoretical age of the universe, a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant.
The only thing that can be said is "it might be possible" given the limited human capacity for understanding things so large.
Perhaps it is better to go with the Buddhist method - accept that we can not know (and stop saying it!).
Incorrect Neospooky.
The key to the original statement, "given enough time" makes the age of the universe insignificant. In fact, since "given enough time" can be any amount of time between zero units and unfinity, the probability of the monkeys typing anything that is suggested (i.e. sonnets, bibles, novels, etc.) is effectively one (or 100% if you do not have a background in probability).
This is, of course, assuming the pressing of keys is essentially random, and "not taking into account the propensity for a monkey to repeat keys" as you did.
The bottom line is very large numbers (or very small probabilities) are not really relevant when given an infinite amount of time.
The conclusion, therefore, is that the statement that "a monkey has a chance of randomly typing any Shakespearean work so miniscule that it is mathematically insignificant" is an incorrect statement when the proper parameters are instituted.
Thanks StatsMan! I guess we statisticians see things the same way ... well, at least issues relating to laws of large numbers! But in all seriousness, suppose that by chance and luck alone I happened to stumble onto something brilliant, and defeat a much stronger player, totally out of character with my other games. For this I get banned? McCarthy is alive and well?
I have thought of this myself. Most of all all have games in us in which we can defeat much stronger players. However, to get banned from this site you would need much more than one "perfect" game. The staff would look at your body of work, as opposed to a single game (small sample size).
So everytime I miss a mate in 2 or hang a rook I think, "at least they know I am not cheating."
If you suspect your opponent has not exactly played fairly, is there anyway of finding out?