In general, when you see teams shuffle around non-starter players in a deal that trades expiring contracts for non-expiring contracts, you usually see any draft considerations going to the team taking on the longer salary commitment. The Celtics gave up a pick to move Courtney Lee. The Celtics received picks when they dumped the expiring contracts of Brooks and Crawford for Joel Anthony (technically expiring, but with a player option that seems guaranteed to be picked up, effectively not).
That's why I think it is a bit silly to expect to trade someone such as Brandon Bass for an expiring contract and a pick and/or a young player. For there to be a chance of that to happen, you'd probably either need a team desperate to salvage playoff hopes damaged by injury and willing to over play or have to get a guy back who makes a few million more than Bass so that the other team saves on luxury tax in the short term.
Most teams are pretty stingy about giving up first-round picks, so if you want to trade guys such as Humphries or Bogans, you probably need to take on future salary commitments if you want to get a pick out of the deal.
Could Bogans be part of a deal involving Denver and Andre Miller? The Nuggets were said to have declined a deal with Sacramento because they didn't want to take back Travis Outlaw's contract for next season. Imagine, for example, Jimmer Fredette and Keith Bogans to Denver, Travis Outlaw to Boston, and Miller to Sacramento, with at least one second-round pick going to the Celtics.
Another possibility would be Detroit sending Jonas Jerebko and his player option for next year to Boston, and Bogans to a team looking for cap relief that sends Detroit a useful player, while the Celtics get draft considerations for renting out next season's cap space, with Joe Dumars prepared to overpay to save his job.