pfstracker.net is amazing.

[Abraham Z]

For anyone still on the fence about this, for scheduling the next game day at My Parents Basement, I searched for 1-5 scenarios that none of our regulars had played. I got a list and it took me 10 seconds to find something on the list that I had already played. Made choosing a scenario for the game day very fast and easy. But of course it's only as effective if the player base uses it.