I have to be in the mood for it and I can't stand music in general that sounds way too similar and monotonous all the way through so that can knock out a fair amount of bands.

Well, while I tend to dislike most prog-metal I absolutely adore Mastodon. I saw them in concert with Dethklok and became a fanatic after almost being moved to tears. Yeah that's right, metal can make me cry :sweat:
I also dig Between the Buried and Me (another example of random metal that can make me cry), Baroness, Dirge Within, Cynic, Draconian, Tiamat, Giant Squid, Galactus 77, A Dark Halo, Dio, and Iron Maiden.
I also love hair metal like Poison, Whitesnake, Twisted Sister, Def Leppard, Van Halen, Motley Crue, and Winger.
And in terms of weird metalish bands, I am in love with GWAR. I would do anything and everything to those men. Going to see them for the third time on Sunday!