Usually a "small, mellow, room" verb. That's kind of generic sounding I know, but it depends on the song mostly. I usually run my drums through Sonitus:FX Reverb, or Waves TrueVerb. Usually I go with a quick decay (1/2 second or so +/-), and adjust the damping, pre-delay, early reflections and others by ear. I generally run all the drums through the reverb equally unless something needs to be more present (i.e. snare), in which case I run less reverb for that track. Sometimes I set up, a second reverb with a slightly longer tail for the overhead or toms to give a little more body during fills.