Play drum over your favorite song. Click on different drums or cymbals to get different sounds, or use the following keyboard keys to play:

[space] - basedrum
[f] - snare
[r] - tom1
[t] - tom2
[y] - tom3
[u] - tom4
[4] - splash
[5] - cymbal left
[8] - cymbal right
[j] - hi-hat
[k] - ride
[g]- cowbell

Check the preference window for more keyboard options. Activate mulitple sounds if you are on Windows via the preferences.