To remember his greatness, the following was an ingenious play by him when he played against Donald Byrne in 1956
photo from chessgames.com
In the above, Fischer's queen was being attacked by the white bishop at c5. Instead of moving his queen away, he sacrificed it by moving his bishop to e6! In exchange of the queen, he gained massive attack opportunities with his minor pieces and finally won the game.
For those of you who don't know how to play chess, the queen is the most powerful pieces from your army and it's a big decision when you choose to sacrifice it. Despite this, Bobby Fischer had the insight to foresee that the sacrifice was worth it. (If you're interested in the complete game record, you can see it here)
Rest in peace Bobby!