Gorguts, Spawn of Possession, Behold...The Arctopus, Electrocution 250 (Metal and Cartoon music, what's not to like?), anything with Ron Jarzombek in it, Gory Blister.
I don't know if I'd say all of these are "experimental" but these albums have many an odd riff and abstract passage.
Gorguts - Obscura
Adramelech - Psychostasia
Demilich - Nespithe
Blut Aus Nord - The Work Which Transforms God (has a slight industrial touch)
Carbonized - Disharmonization (I'm not even sure if I like this but it's the definition of "experimental")