I thought I might add a few cents to this writeup by giving a few examples.
Marilyn Manson
While his music may not be particularly innovative, the lyrical side is by far one of the most potent and philosophical explorations into human nature that you could ever want for - unless you're a theology or philosophy scholar with a photographic memory of Also Sprach Zarathustra.
Majority of fans: Idiot guests on Jenny Jones.
Slipknot
Highly aggressive and loud band. Firstly, any hardcore band who can get 9 guys together in a room and make some coherent noise is a band to be reckoned with. And to top it all off, their rhythm section - consisting of a drummer and two percussionists - are responsible for some of the most mindblowing rhythms this side of the century. While the guitars fare with the usual grind of one or two powerchords in rapid succession, the DJ and sampler offer some truly creepy atmospheres (instead of just grinding away in the background), and their lead singer can go from the throatiest scream to the clearest singing voice in a split second.
Majority of fans: Metalheads who compare scars with other metalheads.
Garbage / Orgy
While these two bands appear to be a bunch of image-driven sellouts, the truth is that their grasp of studio wizardry is unbelievable. Never have you heard finer, crisper production; nor will your search for sensible and instantly pleasing song construction need to look any further.
Majority of fans: Reclusive teenagers with gender-deciding difficulties.
Nine Inch Nails
Trent Reznor may be depressingly one-note in his lyrics, but his skill for songwriting is, until now, unsurpassed when it comes to one-man bands. Both multi-instrumental and a skilled vocalist, Reznor is capable of portraying a soundscape of disillusionment and desolation with such intricate perfection that a chill runs down your spine. He is also one of the few artists in the known universe to perfectly bridging the gap between the reclusive industrialists and the mainstream listening audience.
Majority of fans: Woe-is-me teens with angsty suicidal tendencies, who write shitty poetry and feel depressed for no good reason other than going through puberty.