Twice, but I cannot provide either of them for demo.
1) In the late '90s I was playing a little game called Dark Earth [http://en.wikipedia.org/wiki/Dark_Earth_%28video_game%29], which none of you have likely ever heard of. The game sucked, but it had a ridiculous amount of voice acting, all of which was easily ripped from the files. These dialogues were innocent in their nature, such as "On your knees" (before the Provost), "He touched the snake" (opening a passage in a ruined temple), and "*mouth full* Oh wow, this is good!" (bribing a guard with a food item). Using these innocent files I set about creating a new, 4 minute dialogue, and backing it with a remix of Therapy's "Teethgrinder [http://www.youtube.com/watch?v=oH_yivWallk]", made famous by Road Rash. I titled this piece of perversion "Prison Sex 44". You can deduce the rest. It was a hit among my friends, but that isn't saying much. The finished piece has been lost for eight for nine years now, sadly.
2) A friend of mine needed some music for a PVP video a couple years ago. For this I simply edited and spliced three tracks, added some violin, and agonized screams (mm.. I love me some anguished screams... can listen to them for hours). The mix began as ICP's "If I Was A Serial Killer [http://www.youtube.com/watch?v=gy7BlY2Xa7E]" (first minute or so, piano), delved into Infected Mushroom's "Meduzz [http://www.youtube.com/watch?v=r7C3OHQa0VU]", converged with Infected Mushroom's "Stretched [http://www.youtube.com/watch?v=XhTu_tU__Yg]", back into "Meduzz", and then finished with ICP's track again (ending verses, piano). I called that piece "The Trellis". Can't legally upload it, and I don't have or desire a Youtube account. So oh well.