There were plenty of us around here, myself included, who were expecting a lot more pure salary dumps last year than ended up occurring. The Kevin Martin trade is a pretty good example; Houston got a very good (albeit one way, and significantly overpaid) player, and Sacramento got cap relief via T-Mac's expiring contract.
They also got Carl Landry, a very good, cheap talent. We don't have many of those.
The only real salary *dumps* I can think of off the top of my head are the recent Hinrich deal, the Kurt Thomas trade of a couple years ago, Richard Jefferson to the Spurs last season (which San Antonio wishes they never did). The expiring contract is nice, but unless you've got attractive assets to pair it with (#5 overall pick, Big Al Jeff, Delonte West, etc), it's usually not enough by itself to get anything good done.