I've seen some really cool furniture whose roots were made from thrown away parts. My favorite thus far have been from Sean Woolsey & GDB (Garza Design + Build). Some of you may know Garza's work from the cool furnishings from the Thunderbird Hotel in Marfa, TX.
desk lamp made from reclaimed wood, rusted pans & galvanized pipes
chandelier made from a salvaged wagon wheel
dining chair made from reclaimed steel