Aside from playing crashRun while testing, I've been playing a few other roguelikes lately.
DoomRL - a 7DRL project, if I recall. It's a roguelike tribute to Doom. Lots of fun, and it has a lot of ideas that are relevant for crashRun, primarily in the firearms and targeting.
LambdaRogue - a semi-graphical roguelike that's really interesting. Lots of character development options that I haven't really been able to delve into.
Frozen Depths - I compiled the OS X version of the game for the programmer who makes this one. It's intended to be a fairly simply hack-n-slash game but it's also a lot of fun. A neat twist is that the deeper you go into the dungeon, the colder and colder it gets so you have to find ways to keep from freezing to death, in addition to bashing the monsters you happen across.
Oddly, I've been staying away from the classics a bit lately. It's been a while since I've run a game of Nethack or Angband. I'm not sure why; maybe because they take a bit more commitment from me.