pistons, cas, map sensor,injector, loom, ecu and I/C from a 4agze, then strap a turbo on the side, run some oil and water lines, and plump in the I/C and you have yourself a relatively cheap turbo setup.
thats if you rebuild or you can do a similar low boost turbo setup on a standard 4age using all of the above (minus the pistons) and have fun till it pops :P
just depends on how fresh your 4age is or how cheap you want to do things
anyways I'm getting way way off topic here :P
Edit:rad32, i've changed the topic so that it suits the discussion