What strange chess rules can you think up?

it should have a piece called rajnikanth. in one move, kills all pawns, knights, bishops, rooks, dethrones the king, and gets the queen pregnant :-)

I'll add a Lanister on the board so that it can eliminate any piece, then pay back material worth in pawns because they always pay their debts!

This is one of my favorite ideas.

Yeah I was going to sugest that myself, except that if a players King is taken, then the player who took it may also take another piece off the board (can't be their Queen).

White plays e4 then slaps his opponents face then  presses the clock..and vice-versa. Whoever checkmates gets to punch the other with an upper-cut.

I think this is good. Take back move allowed once every game for the lower rated player. This gives the lower better chance to beat the higher rated opponent. 

Actually we used to hold this kind of tourneys within our circle of friends in Israel, many years ago... there was a system of odds giving - 

You either gave pawn and two moves, plus one takeback during the game, 

or a knight and two takebacks (cumulative on the same move, or at two different points in the game)

Or A queen for a bishop and three takebacks

Or - a queen and four takebacks, where the odds giver has two minutes and the odd receiver, five, and in case they both fall under a minute, the odds receiver receives an extra minute, the odds giver, an extra ten seconds. 

- - - - - - - - - - 

This relates to another version of blitz which I call 'cool blitz', and which is designed to avoid last-minute time scramble, heart break and the feeling that the result of the game was random - 

in this version, each player gets five minutes for the entire game, but if BOTH players fall under a minute, they BOTH receive an extra minute. 

For example, if you have 18 seconds and I have 1:02 minutes, we just keep playing. Then if you remain with 13 and I fall to 59 seconds, now that we're both under a minute, we both receive the bonus so that you will have 1:13, and I - 1:59. Of course this can happen again and again during the same blitz game, and you never reach a last-few-seconds violent time scramble between the players. 

Of course we can still have a time scramble when you have, for example, six seconds, and I have 1:05 - you don't want to lose on time, and I don't want to go under a minute and save your skin...

but in this case if you lost you can't complain - you used a full minute more than I did, so there was really nothing random about the result, which makes the entire difference with a 'conventional' blitz time-scramble.

This can be incorporated in chess.com as an experimental time control, or type of clock, called Solsky clock (like you have Fischer clock and Bronstein clock, for example). Instead of determining time and increment as in Fischer's clock, you will determine time and pull-back point (for example, you can play 5 minute blitz, and when both players go below 2:30, both get an additional 2:30, or even 3 minute blitz, and when both player go below 0:15, you add 0:15 - and of course many other possibilities exist along these lines). 

Herson my kabayan. Magsalita ka naman diyan puro ka react. Sali ka sa group natin now na!.

Saan?

Maybe pieces having 2 special skills, I have only thought of the pawn's, please help me on the others
Pawn skill 1: Selfdestruct-sacrifice the pawn and destroy all pieces(B or W) in all its adjacent squares.

skill 2: Protect-the pawn is temporarily invulnerable for one turn
Now we know who's a fan of classic RPG :D 

Amp... what about,if their are 3 kings to mate!

That would be like a replay, but taken from the point of the begginers blunder.

The Touch-Move rule: if a player attempts to molest their opponent before a checkmate is declared, they must immediately move out of the playing area.

How about getting the king to the 8th rank as victory? Similar to "Games of the General". There will be new tactics and strategy if this is implemented.

How about a version of Chess based on Team Fortress 2? Called "Team FortChess".

The pawns are Soldiers, the queenspawn and kingspawn are Scouts. The rooks are Engineers setting up their sentries. The Knights are "demo-knights". Queens bishop is the Sniper, and Kings bishop is the Pyro. The Queen is Heavy, and the King is Medic.

Each player marks a small dot under one of their opponents Soldiers, that pawn is a Spy. At any time, instead of moving, a player may "Spy-check" a pawn of theirs that is in a 1 square radius of their Pyro or Sniper (with Jarate). If it is found, it is removed from the board.

Soldiers may rocket-jump once at the start (like a pawn), Scouts may double jump every turn.

A pawn may not be "Spy-checked" if it is still on its starting sqare. At any time, instead of moving, a player may have their own Spy take an opponents piece as if the pawn was taking one of its own (it cannot take towards their opponent or sideways). A Spy may also be revealed in order to refute it taking a pawn from its own team 'en passant'.

Only Soldiers may promote, and only into either Engineer, Pyro, Sniper, or Demo-knight. When a Scout reaches the end of the board it picks up the "intel" and starts returning to base (it may still double-jump per turn). If it reaches its base with the intel the game is won. If the Scout carrying the intel is killed, then the intel is dropped on that square. After the intel is dropped it may be picked up by any piece (but that piece may only move 1 square back to its base). If the intel isn't taken in picked up in 2 turns then it returns to its King square.

The game is not won if the Medic is taken, but rather when all the pieces are taken, or when a player retrieves their opponents intel.

Minesweeper chess, there are 4 bombs hidden in a square each in the squares a3 to h6 whereby landing on the square destroys the landing piece, the square is then used normally.