I've only ever heard of a turbo feeding into a blower. It got to be a pretty complex system but apparently pretty impressive. My book on Engine Management Systems has a "compound Forced Induction" chapter in it. They took a toyota MR2 engine and put a turbo feeding into a blower. Amazing beast apparentely. Soon as you put your foot down she went from a gas sipping v6 (3.0L i think) into a torque beast. The blower carried the engine into the 3500 RPM range at which point the turbo made enough boost that the super belt was putting power BACK into the crankshaft. Fast!
