Collusion in poker - can it actually acomplish anything?

[SplawnDarts]

I've noticed a continual gripe of internet players is the possibility of collusion. I've also heard occasional gripes about it in B&M joints.

However, I've never heard anyone propose a poker scenario where collusion is particularly +EV to the net bankroll of those doing it when compared to the oportunity cost of forgoing other legal (and usually simpler) strategies that could be applied in the same scenario. Anyone got any concrete examples?

The best I can think of is two colluding players with a victim between them repeatedly re-raising eachother when one of them signals they have the draw-proof (or nearly so) nuts. You might get a bet a session on average that way???