I really like the AC Booster: http://www.xotic.us/effects/
I'm not a big OD guy. I like Xotic because they give you bass and treble controls, I sometimes have issues with pedals with a tone control only. I prefer the single pedals over the + versions. AC does a nice job from going from a boost pedal into decent level gain OD.
Although, I've really been wanting to try a Lovepedal Eternity burst.