Best bet is to either check to Villain and see what he comes out with, or probe bet with about a 1/3 of the pot... If he is a maniac type of player, these are the spots where they're looking to get paid off handsomely if they did hit the trips, so usually they'll shove all in on either the flop or the turn. If you've committed about 1/10th of your chips to this pot, you can still get away from this relatively unscathed... and that is something you should be paying attention to pre-flop, that you haven't overcommitted yourself to a possible trap.
On the other hand, if you have a really good read on him (which is still difficult for the ultra-LAGs, as the really skilled ones know how to keep both their bluff and monster betting patterns the same), then a 3-bet on the flop is called for. But it woudn't be the most ideal spot to pick off a bluff, especially because LAGs have a wide range, and they could be re-raising pre-flop against one or 2 opponents with any suited connectors, Ace-rag, medium/low pair, etc.