Mike Wallace, WR
An unrestricted free agent this time around, Wallace is the talented, top-flight wide receiver every NFL team covets. He's coming off a contentious year with the Steelers following a holdout that lasted through training camp. So you can be sure he's expecting to get paid.
If the Patriots ever want a field-stretching wide receiver, one who specifically can extend plays vertically as has been demanded, then Wallace is the man. He ran a 4.33 40-yard dash and his 17.2 yards per catch career average is exactly what Patriots fans want.
At 26, and in the right situation, he could be good player for a long time.