Check raising the flop

I feel like I check raise to little, particularly on the flop. When do you do it and against what opponents do you do it?

I know what you mean. I do it more than I used to though. here's some spots I can think of...
one spot is vs someone who limps the co/btn then bets when checked to a lot.
or similarly, vs a tag that chronically cbets but isn't likely to go further as a bluff. I usually just lead out in this spot though.
another spot is in relative position of the pfr with a good draw or made hand, for example you call an utg pfr with 33 in the bb after 2 more callers. flop gives you a set. if the pfr is likely to bet, then check and hope to raise after 1 or more ppl call.

a set on a draw looking board versus a player likely to have some sort of overpair.

Puts them in a dificult spot.