I have a new favorite tire: Kenda K-RAD
They are stupid cheap, like $12 each at Amazon
They are primarily used by BMX riders and now I know why. They don't seem any heavier than the Smalll block 8's I was using before. They are pretty wide and seem to be wider than the sidewall states(26X2.3) They have big knobs but a relatively low profile. They roll faster than any treaded tire I've used off-road and roll very well on concrete also. I was concerned that the downside would be a lack of traction but I just used them and thrashed them hard at Boyette twice and I never spun out or lost any confidence in my traction on any of the trails.