[danq]

Edited my first post - I can't count.

For the two-pair-or-set probability, rather than inclusion-exclusion, I just calculated cases. There are 15 out of 37 cards that pair the board. If nobody beats you, there are four cases: nobody has a pair, one hand has one pair, two hands have one pair each, or all three hands have one pair each. Each of these is easy to calculate, then add.

Dan