I see Sactown, NY, Houston, and Dallas as the best possibilities probably in that order.
I wouldn't be surprised to see SacTown push for Rondo and Smith and role with Rondo,Gay, Smith, Cousins.
NY could make the push to add a star next to Carmelo, however Rondo's shooting in the triangle could be interesting.
Houston has been looking for a star PG for quite sometime. Harden is such a dominant ball handler though, I'd be surprised to see them work out.
Dallas would be awesome but I don't think they have the players to make it work. Imagine a starting 5 of Rondo, Ellis, Parsons, Dirk, Chandler....That would be silly good.