Jonathan Feigen of the Houston Chronicle writes that the Rockets have two commodities playoff teams are especially interested in: Walt Williams and Kevin Willis.  They are attractive because they are vets who can contribute to a playoff run, and yet have contracts that expire this offseason so they won't affect long-term cap situations.  The Rockets have been trying to get first round picks or long-term building blocks without taking on unwanted long-term contracts.  Because of these stipulations, they probably won't be able to get a deal done.  The Spurs and Mavericks have expressed interest in Willis, but can't match his $3 million contract without sending a long-term contract.  Williams makes $5 million this season.