Besides some great bands mentioned,
BORIS
I saw this guys a few months ago and they were incredible. So much more versatile and daring than many of their colleagues, definitely something any rock fan could get into. Check out their collaboration with Michio Kurihara called "Rainbow" and their album "Pink."
OM
These guys are the rhythm section that remains from the great stoner rock band Sleep. Note Al Cisneros' 6x15 Green cabinets!
And now for two Minneapolis bands worth checking out:
ZEBULON PIKE
http://www.zebulonpike.com/CASTLE
http://myspace.com/castledoomA friend's band. Note their unabashed MC5 influences!