http://espn.go.com/nba/tradeMachine?tradeId=aspf28jTrade 1: Spurs, Celtics, Hawks, Suns
Spurs receive: Kevin Garnett, Jared Dudley, Leandro Barbosa
Celtics receive: Josh Smith and Corey Joseph
Hawks receive: Kawhi Leonard, Dejuan Blaire, Stephen Jackson, and Bos 2nd rounder
Suns receive: Kyle Korver and Bos 1st (protected top 20)
Spurs do this because they see OKC and LAC and realize the time to win is now with this group. Pair KG with Duncan and have Dudley as the SF. Barbosa contributes off bench.
Celtics do it to pair Smith, who does an extension, with Rondo and understand they can not contend currently with this group. Also Kg decides to go to a similarly built organization to try and win.
Hawks do it because Kawhi is a nice prospect, fits their team, and is on a nice contract. They couldn't ask for a better player in return for Smith - who they really don't want to pay.
Suns do it because they get a future pick and some cap relief with Korver's expiring contract and they might want to resign him.
http://espn.go.com/nba/tradeMachine?tradeId=a8yzonnTrade 2: Memphis and Boston
Celtics receive Rudy Gay and Jerryd Bayless
Grizzlies receive Paul Pierce and Jason Terry
Celtics do this to form a core trio of Rajon Rondo, Rudy Gay, and Josh Smith. Bayless has one year less on his deal then Terry.
Grizzlies do this because Pierce brings similar production to Gay but also provides the cap flexibility for next year do to his deal and Memphis values having that option. They also get Terry who is an upgrade over Bayless.
The Celtics would have three All-Star Caliber pieces entering their primes. They then have other assets and pieces they could move in the future to build around these guys. Bass, AB, Sully, Green, Melo, and Lee. Maybe they look at packaging Green, Lee, or Bass with Bradley or Sully for a Center. Maybe Gortat in a separate deal with Phoenix. I don't know, but we figure that out in the off-season.