There are only two players I would trade Pierce to the Nets for and I don't think the Nets are going to move Deron Williams or Brook Lopez for Pierce. If I'm Boston and I want to go into rebuilding I might consider the following trade:
Pierce, Green, Bass, Terry
for
Wallace, Humphries, Evans, Taylor, Teletovic, Brooks, Blatche, 2013 1st
Basically clears out Boston's dead weight (and Pierce which would hurt) for Wallace's dead weight (smaller combined and more easily moved in the future), Humphries next year expiring contract (making him very valuable this summer), and a bunch of young guys (or vets on good deals).
Probably wouldn't do it, but I wouldn't immediately hang up the phone laughting either.