I haven't seen his name come up too much, but what about Jarrett Jack? He is a restricted FA this year, and I have heard mixed things about whether he is in the Pacers future plans (they are reportedly looking for PG's in the draft this year, and already have Ford).
I know he doesn't play the biggest position of need, but he wouldn't be a bad player to take a look at. He would give us a very good backup PG, and he also could be very good playing next to House, since he is big, and a good defender. He should be able to cover most backup SG's in the league...and could be valuable covering guys like Delonte West and Courtney Lee, who will likely be standing in the C's way to another championship.
Now, the big question is the price. It may take something close to the MLE for the Pacers not to match an offer to him, but they could concievably be a good match for a sign and trade. If the C's are not looking to keep Big Baby, he may the the type of player they would like to add to their team.
While Davis is not a great athlete, he is a very fundamentally sound defensive player, who I think would excel in Jim O'Brien's defensive system (which is of course very similar to the C's system). He also has an offensive game, which may fit in well with the rest of their lineup.
So what might be worth looking at would be signing and trading Davis for a signed Jack. And if we want to get really creative, we could make this deal bigger, including some of the expiring contracts the C's have for either someone like Foster, or maybe even a Mike Dunleavy.