I could see Ainge making something like this happening... (Plus Jack would be a good replacement obtainable PG if we had to part with Rondo. Yuck the thought makes me sick!)
http://espn.go.com/nba/tradeMachine?tradeId=admwaza(Edit* link should now work! Thanks BudWeiser)
With the main players being (And just these four in the deal working in trade checker):
Rondo to the Kings
Cousins and Jack to the Celts
Evans to the Warriors
The Kings would probably want more however.
Back to that deal however. Kings and Warriors swap Bierndnies and Salmons. 2 not so great contracts for either team but the Kings save one year on Bierdnis's deal and give them an extra big man.
Jack/Terry
Bradley/Lee
Pierce/Green
KG/Sully
Cousins/Wilcox