Parker as a #2 or #3 on a team that has a good QB and a good WR or two might be productive. He isn't a primary WR which is how the Pats used him a lot. But I can see him in a role like how the Pats used Stallworth in 2007. Stallworth and Parker are very different WRs, but Stallworth was a defacto #3 (although a starter) who was really only used to make a handful of big plays a game.
I don't think the Pats will get anything more than a late third day pick for Parker, but I can see someone taking him off the Patriots' hands.