Fugazi and Shellac are old favourites that I still listen to frequently. Converge and Dillinger of the newer breed, and The Locust.
Still got some early Rollins Band, and some old Aussie stuff like Budd, Paintstripper and Ricaine, but don't listen to them so much any more. How about Treponem Pal; remember them?
The Young Gods are a perennial favourite, their early stuff was kind of hardcore industrial, especially their first album. I drag out some early Helmet once in a while, as well as Prong and Corrosion of Conformity.
You can probably tell there's a big hole in my collection. I lost track of harder music from the mid nineties for about ten years. These threads are great for finding out about unheard stuff.