[Copernicus]

very roughly I get about 4400/1, although that seems a bet more likely than I would have thought.

The probability of any pair being dealt to a player is .0588. The probability of 3 players being dealt a pair is about

(.0588^3)*C(10,3)=14.66%. (I didnt force the other 7 to not have pairs, since there could have been more that folded to the pre-flop action. Also this is a little low because as pairs are dealt it becomes a little easier to deal another pair). So say 3 or more pairs will be dealt 15% of the time. A single pair has an 11.5% chance of flopping a set, so to flop 3 sets its roughly .115^3 (again thats a little low because of the existence of the other pairs/sets) or .15%. .15*.0015=.0000225 or 4443/1.