I know that Rondo to DAL has been called "ridiculous" by sources but I still want to discuss it because it makes some sense for both teams.
DAL obviously is looking to entice DHoward and now that CP is most likely staying in LA, Rondo is the obvious next piece for DAL to look to acquire in an effort to assemble a Big 3 of their own. DIrk, DH, and Rondo is a nice core for DAL to build around.
BOS trading Rondo is certainly questionable depending on Danny's overall plan, but if he is looking to go after the top of this 2014 draft, then he really does need to move Rondo IMO. And he needs to move him for talent that won't create a similar problem (ie make us too good to bottom out for this draft class).
So, with that said, my idea is:
DAL gives:
Larkin
Ledo
Marion (expiring)
Future #1s
BOS gives:
Rondo
Larkin and Ledo are two nice prospects and Marion's contract will be off the books after this upcoming season. also adding to Danny's stockpile of first round picks.
DAL gets Rondo while not adding salary by unloading Marion. Thus, they still have room to sign Howard.