Jason Collins and Leandro Barbosa to the Washington Wizards for Jordan Crawford.
This is a good move for the Celtics, who were able to clear some deadweight from their roster and get a solid scorer in return. They won't miss Collins (who's nothing more than a scrub at this point in his career) or Barbosa, who's out for the year with a torn ACL. Given Barbosa's injury and expiring contract, it's unlikely that he'll ever play a minute for the Wizards, who just made themselves worse (if that's even possible).
Danny Ainge probably should have focused on bringing in a big man instead, but Crawford should be a nice pickup for the offensively-challenged C's. The athletic shooting guard is streaky and lost playing time in Washington following John Wall's return from a knee injury, but he's still a useful player. Crawford can score points in bunches (nearly 18 per game from November 14th through January 4th), has developed a decent three-point shot and, most importantly, can dunk over LeBron James. He'll extend the bench for Doc Rivers while infusing some youth into one of the NBA's oldest rosters.
In what turned out to be a quiet and disappointing trade deadline (no Josh Smith trade?!), there was only other one real move of interest. The Orlando Magic sent J.J. Redick, Gustavo Ayon and Ish Smith to the Milwaukee Bucks for Tobias Harris, Beno Udrih and Doron Lamb. The Bucks, currently in control of the eighth seed in the East, drastically improved their bench by stealing one of the NBA's top sharpshooters. The former Blue Devil was in the midst of a breakout season with Orlando, averaging 15.1 points per game with 45-39-89 shooting splits as the Magic's second best scoring option behind Arron Afflalo. He won't get as many touches playing alongside Monta Ellis and Brandon Jennings, but he has to be ecstatic about escaping the second-worst team in the NBA (they really were just Dwight Howard and a bunch of guys) and climbing aboard a legitimate playoff contender.
As for the Magic, dealing Redick might be just what they need to sink below the Charlotte Hornets in the standings and improve their lottery odds. You can't blame them for trying.