CO is a complete moron (69/51/3). His 3-bet just means he still has 2 cards. Button is unknown.

Poker Stars
Limit Holdem Ring game
Limit: $0.50/$1
6 players


Pre-flop: (6 players) Hero is UTG+1 with
UTG folds, Hero raises, CO 3-bets, Button calls, 2 folds, Hero caps, CO calls, Button calls.

Flop: (13.5SB, 3 players)
Hero bets, CO calls, Button calls.

Turn: (8.25BB, 3 players)
Hero bets, CO calls, Button raises, Hero ????

The thing I kept coming back to here was his calling 3 bets cold pre-flop. What hands does he do that with that I'm beating? Is it worth 2 (or more) BB to go to a showdown?

If he's a good player then I may call him down, but if he's an idiot, like you seem to think he is, then he probably has a Jack. His thinking probably goes like this....

Preflop...I have 2 cards. They both have pictures on them. I call.

Flop.....I have top pair, but other people keep betting. Hmm, could they have a better hand? I think they're all bluffing, but I'm just going to call just in case.

Turn.....Now here's another Jack. YAY I WIN!

I think there is much more of a chance of a bad player having a Jack here than a solid player.

I'd have to agree with MK here. Against an unknown I would probably have to muck. I wouldn't be suprised to see something like AJ or even a PP where he flopped a set and just filled up. I also wouldn't cap PF since you'll be OOP post flop against 2 behind you. If it were just you and the maniac I wouldn't mind it as much. Unless button is also an ubermaniac also it takes quite a set of stones to pop the turn with all the action.

I occasionally get into a mindset that "button sees a big pot has position and is doing whatever he can to win it". I tend to find that I'm wrong in those situations more often than not.