basicly P2P is legal as hell. Its only thing that makes everybody jumpy, is that you can share stuff (and thus offer, which is not legal....) that must be bought.
Its the same as lending a cd to someone, its illegal. (don't believe me? Check ur disk... or the manual... its everywhere
).
Besides that, you can share everything you want. Your own made documents, movies (home made.. erm... some refer to pr0n then... :
) ... etc.
As always the problem is not tackled by its roots, but by its symptons... sheesh