Whats the most silly, illogical thing you've done involving chess?  For me it has to be back when I was 1250 deciding to pick up the modern defense because it was "modern".

P.S. I'm back after a long hiatus!  Although the only memorable thing I did was insane overanalysis during vote chess.

Blundered.

Making moves whilst not entirely the paragon of sobriety thinking I was constructing a devastating brilliancy. The cold light of day is harsh.

About four weeks ago during a league match I pulled a pawn.

The opposite of pushing a pawn. I pulled the pawn towards my side of the board.

1. About an hour before setting off for the game I almost knocked myself unconscious in my flat picking up my son's building bricks and standing up in the wrong place.

2. I had been two pieces up at one point and was now fighting for a draw.

The answer as to why I should think that was my move lies somewhere between these two facts.

My opponent quickly moved my pawn back and said, "it's going this way, buddy."

Well I remember once, about a year ago, I had a quick forced mate in a correspondence game.  Why my opponent played on is beyond me but with mate in two I ended up ignoring the move order and my nice 'mating net' ended up hanging my queen to a pawn.  I went on to lose! Probably my most emberassing moment.

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In an OTB game about a month ago, we got as far as 1. d4 g6 2. Nf3 Bg7 3. e4 d6 4. Be3 Nf6 5. Nc3 O-O 6. Qd2 c6 7. Bd3 b5 and for some reason I got it into my head that the book move was e5, so that you can stash the knight on e4 when the pawns come forward (what?).  I knew I'd researched this specific position and the only move jumping out at me from the depths of my memory was e5, so even though I could see at least 3 things wrong with it, I played it and presumably figured I'd work it out on my opponent's time.

I never see simple stuff, I always look for more complicated solutions.

 

Here my opponent resigned, and I made smart remark how I saw mate in 4 -1...Rg2+ 2.Kh4 Rxh2+ 3.Kg3 Rg2+ 4.Kh4 fxg5#. And then he told me that I could mate him after 2.Kh4 fxg5#. I felt so stupid. And I do that more that I would like to. 

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lol I know how you feel with that one! Only a few months ago in an OTB game my opponent put me in check with his Knight, but for some reason I didn't even notice I was in check! He got up from the board to take a stroll around (he was winning at this point), and about a minute later I made a Rook move as if I wasn't in check! He was still gone from the board and I think he'd left the room at this point with his clock running. To my puzzlement and annoyance people were coming over and trying not too subtly to hide their sniggers. I was thinking to myself "OK, I'm losing by quite a bit but what's so funny about that?" So when eventually after about 5 minutes I realised what had happened I wished the ground would literally swallow me up! Although I did manage to swindle out a draw in the end from the mess somehow!

I played the game.

In my first tournament, I won my first two games, then moved on to play an expert. I ripped up his queenside with a knight sac and then stole a rook and pawn. As I prepared my final attack, rather than resign, he sank into deep thought and then proceeded to play some rather mysterious pawn moves. I overconfidently dismissed his efforts as desperate and useless until I actually decided to take a look at what he was doing and realized that I was lost in 7 moves! After playing it out, I shook his hand and walked away hanging my head in shame.

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You almost beat an Expert in your 1st tournament?!

I had a won game against Ivanov and got so nervous that I couldn't think and he went on to win. 

I was rated in the 1200"s and found myself  3 and 0 out of 5 and matched against a National Master 2350. Instead of playing my usual Sicilian and giving it my best shot I choked and played the Caro-Kann for the first time in my life. I was crushed in 12 moves. I realize I would have been crushed anyway, but I should have gone down swinging.

I was once playing chess with my cousin and I concentrated far-too-much on a specific problem in my position, I concentrated so much that I made a diagnal pawn move that would have fixed the problem. Needless to say my cousin was like, "What the heck is that man?"