What is your worst chess blunder, share your thoughts!

All chess players can blunder, even G.Ms have on occasions blundered there queen? I started playing chess when I was 14 and over the years I have made my fare share of blunders, it used to really effect me but these days I treat it like Laskers famous Quote: Chess is as life you will have Good days and Bad!? The other day in the early hours nodding in and out of sleep during a game at 2:30 am I made a move which lost my queen for a knight?? Even G.M can blunder too in 1987 I saw a I.M at a congress lose his queen only getting a Rook and a pawn for it and resigning after just 26 moves, it happens to us all even the more experienced wood pushers!