Never Give Up
A lot of the time most players (me included), will resign a game after making one bad move, not wanting to even try to make a come back since they feel they are too far gone. Maybe we should all try to not give up so quickly. Remember, one of the most difficult things in chess is winning a won game, if you keep playing you can put pressure on them, you're opponent might go into an "I have to win mentality and wind up making a mistake.
I was playing in a 3-2 (3 min. with 2 sec. added each move) speed game, early on I made a blunder and was about too click resign, I quickly changed my mind thinking "It's a speed game, it will be over with in a few seconds anyway so just play on." I'm glad I changed my mind since I wound up coming back to win