Experimental analog sampling with modified vinyls.
Sectors from a vinyl record are cut and replaced by pieces with exact shape from other records. When played in a vinyl player the needle follows the grooves from both sectors creating sampled tunes or loops.
More information here: http://blog.ishback.com/?p=918
In this video:
Supertramp – Crisis? What Crisis?
Paul Anka – My Way
Chicago – Chicago X
Lil Jon – Kings of Crunk