Someone I havent heard mentioned is Tracy McGrady. He does have injury concerns, albeit pretty big ones but he is only one year older than Butler who has also had injuries. He would be a nice weapon to have next to Roy as the second option when he is healthy. I have no idea what he would cost right now though..
I'm guessing Caron Butler as he is getting frustrated knowing the Wizards are now trying to get a top three lottery pick instead of wanting to make the playoffs.
I think Ike Diogu is being showcased too. To show he can play.
Wizards want to make another run at the playoffs next season with Arenas & Jamison. So if Butler wants out they will need to fill his position. Maybe a three team deal is in the works in the next two weeks.