NOFX is definatly a kickass band. Metal isn't even so much one genre anymore though, it covers so much.
If your into thrash I'd recommend Children of Bodom.
Also some good straight up heavy metal is Pantera.
I've always been one for Prog stuff. I always dug things like Symphony X and Dream Theatre when I was actually a viable metal head. Dream Theatre might be more your cup of tea, some great thrashing guitar riffs in Dream Theatre though they have a very clean vocalist. Symphony X is more reminicent of power metal to me, but I haven't listend to them in a long while.
Try The Shins and Modest Mouse if you like The Hush Sound. To be honest I can't clearly remember what The Hush Sound is, but my friends that listen to them also dig The Shins and Modest Mouse.
Primus for some more Metal.
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ROW ROW FIGHT THE POWAH