Originally posted by Data Fly
Apparently she needed a draw to qualify for the next round and so went for a perpetual.
Here is a picture of how she looked after 57. ... Qxa5
(the 2007 refers to her rating - after this game FIDE held a special meeting and stripped her of nearly 400 rating points for bringing the game into disrepute).
They didn't really do that did they? As blunders go it's pretty spectacular, just because it both misses mate and drops the queen, but I can dig games out by all the great names where they've done something dappy. This is Karpov - Christiansen, Wijk aan Zee, 1993: