When I have a real hand, I bet the pot about 90% of the time. However, sometimes I have a good but non-nut hand where I want to raise a bettor, but still be able to fold to a reraise. When I want to do this, I see how much it would be to bet the pot, and then take off one of the high digits.

For example, let's say a MP player who's fairly deep bets the pot into me, and I have bottom set. If a pot-sized reraise would be $560, but I don't want to commit myself to the hand, I just raise to $460. Since it "looks like" the right amount, my opponent will usually assume that I bet the pot, even though I actually didn't. Just something different to play with.