I wish playchess.com had a 'moretime' feature.
On ICC, I punish hate-waiters by continually giving them more time. They are forced to either resign or continue staring at their lost position. The best part is, they can't play any other games on the server. I've broken the spirit of even the most stubborn hate-waiters in this manner. One guy tried everything. He disconnected, only to find that the server put him right back into the game upon his return. After an hour (!) or so more of more-time'ing, he finally left for the night. I adjourned the game. The next evening, when he was on the server, he tried seeking a game, which also sends an automatic challenge to finish adjournments. I accepted, and went right back to more-timing him.
He finally resigned.