I know, I know, the Steelers don't sign free agents of note. But after two non-winning, non play off seasons, I think this could be the year they do. You say they have no cap room? I think they will be making Troy re-do his deal, and maybe let one other high priced player, who isn't playing up to his contract, hit the road to make room.
Then again, Pgh could stick to their usual plan of no high - or even mid - FA name. (Although they did sign a FEW in recent history, including Duce Staley (huge mistake and I knew it at the time), Kevin Greene (a total no brainer and great move), James Farrior (great move), a few linemen, etc.
So, let's just pretend they might sign a decent FA. Who should they sign? I have a great addition for this team. Brent Grimes. Took a 1 year deal to go to Miami and played great. He is right in his prime, but is 30, so that doesn't fit into the Steeler way; they rarely sign 30+ year old FA. It would be a very solid move. But he was born in PA, something the Steelers over value. However, it's probably safe to say he wasn't a Steeler fan; born in Philly.
If not Grimes, how about Sam Shields? He is 26, so a 4-5 year deal would be ideal.