A few years ago I went in to the basement room where the cool kids hung out while they did video conversions and such. They had a playlist in the background of "Haunting Covers" or something like that. It was a take on all different music, but played in a really chilled, gothic style and by a mix of un/lesser-known artists.
Does anyone have some recommendations? To give you an idea, one of the more known tracks I heard while I was there was Nirvana's Smells Like Teen Spirit but covered by Tori Amos.