I know Larbrd33 mentioned this and I think he's right.
Charlotte is a very good trade partner for Rondo.
They are one of those teams that could use a fringe star to help lead them into the playoffs as they are currently the 8th seed.
They have a good mix of expiring contracts (Gordon, Sessions) young atheltic players (MKG and Biyombo) and they have a 2014 draft pick which is top 8 protected from Detroit, top 1 protected in 2015 and unprotected in 2016.
Something like this could work
Celts get: MKG, Biyombo, Ben Gordon, Ramon Sessions and the 2014 Detroit 1st rounder
Charlotte gets: Rondo, Wallace and Jeff Green.