Chance of hitting a hand on the flop

[Mr Mojo Risin]

What are the odds of hitting a playable hand on the flop? I know that is a very vauge question, since different people have different opinions of playable hands. A rough estimate would be nice, or you just how many of your hands do you continue with after the flop?

[gamble4pro]

Odds of hittting 3 unique cards (for a straight flush, for example): 1/C(50,3) = 1/19600
Odds of hitting a specific suit (when you hold two of this suit): C(11,3)/C(50,3) = 165/19600 = 0.841%
Odds of hitting 3 specific cards (as value - for straight, for example): 4*4*4/C(50,3) = 64/19600 = 0.326%
etc.