Culled from the depths of the Internet: WARPS (World Association for Ruined Piano Studies). A project spearheaded by composers Stephen Scott and Ross Bolleter, WARPS is dedicated to exploring the sounds that can be produced by decrepit pianos; for example, instruments that have been left outside in the rain with no maintenance for forty years.
The "sounds" section, in particular, is worth a visit. Like the prepared-piano Sonatas and Interludes of John Cage, some of the piano notes sound completely normal, others are out of tune or tinny-sounding, and others produce only a dull thud.
Previously: Flaming pianos, shredded pianos.