Sunlion with High Gain transistors - amazing fuzz tone and with the guitar vol at 5, (amp just at break up) the tone is all clean, roll up to 6 and it starts to rumble and the increase the fuzz tone from there, 7 and 8 its georgous tube overdrive, then 9 and 10 smooth fuzz, add the Beano Side and it's focused like a lazer beam :AOK
Depends what you mean by "clean up," but you might want to check out the RonSound Hair Pie '81. Just got one a week or so ago from the forum. More gain than any single pedal I've tried (including my beloved Crunch Box), definitely fuzzy, lots of variation in the tone knob, and responds very well to volume knob changes. At higher gain settings I won't say it gets completely clean with the vol. knob, but it loses its big, hairy sustain and behaves nicely (esp. w/ single coils).
Keeley DS-1 is a surprisingly good pedal, although it's more in the "utility" class than "boutique". Cleans up really well and still rips when pegged. Has a lot of drive on tap too, which not all OD's have.
Thanks very much for all of the input. I currently use an ICBM with my pedal steel guitars and although it can get extremely gainy and smooth, it can clean up a bit. Still looking for a little more "magic".
Use an OCD for low gain to mid gain and it is great with pedal steel.