get a VSTi host, and then google for free VSTi s.
sequence VSTis with the mpc
Then run a line out from your computer into the mpc, and sample cool VST stuff into the mpc...
get a free audio editing program from interweb.
get a midi interface..
download songs from interweb, and either sample directly into mpc(fast, fun),
or edit and process samples in pooter...more accurate, and more crazy sound design tools too, like "reverse sample"
find a MPC program maker for pooter
get a compact flash reader
get ram
get a bigger CF card.