Update: 

The Celtics are considering trading backup center Patrick O'Bryant to the Sacramento Kings, but there is also a possibility that he will instead be sent to the Toronto Raptors in exchange for guard Will Solomon.

Looks like we won't have POB to kick around any more:

The Celtics have traded backup center Patrick O'Bryant to the Sacramento Kings. The move was made for salary-cap purposes and the club will not receive a player in return, according to an NBA source.

There is the possibility that the club will receive a draft pick in exchange for the 7-footer, who averaged 1.5 points in 26 games for the Celtics after signing as a free agent in the offseason.

O'Bryant was not at the Celtics' shootaround this afternoon.

This is going to be the same as the Cassell deal.  We trade a player we're going to cut, along with cash, for a protected draft pick.  That saves us money on the luxury tax, and gives the Kings a little extra cash.