Ignoring any rumors involving the Packers trading a 2nd round pick for Miami's DE Jason Taylor, or showing interest in New England WR Randy Moss (Why would they this year when he was so much cheaper last season?), GM Ted Thompson has inquired about a couple of backups. The 2008 versions of CB Frank Walker.
Detroit LB Boss Bailey
Denver CB Champ Bailey's younger brother entered the league in 2003 with explosive speed while a little undersized at linebacker. Early in his career he seemed like a good fit at weak side linebacker, but he played strong side linebacker last season in Detroit and presumably the Packers interest in him is for the strongside. As the article says, Bailey came out on passing downs, so he would seem best suited as a backup, or to challenge, LB Brady Poppinga. The Packers have little depth behind the starting linebackers, so finding a veteran backup is a good idea.
St. Louis LB Brandon Chillar
Another strong side linebacker who appears to have a few teams interested in him. It's hard to get too excited about anyone who started on St. Louis' awful defense, but he could provide depth and might not cost too much. Still I expect he'll find some team where he'll have a better shot at starting.
Detroit DE Corey Smith
Well he played the last two seasons with Detroit, but he's truly a journeyman. 2007 was his best season and he appeared to play well when given the opportunity. Again, he too played for a bad defense in Detroit. He seems a little undersized, if he truly could backup DE Aaron Kampman or take the job from backup DE Mike Montgomery, he would have to show that he could play either defensive end position. More likely Thompson is looking at him as a backup speed rusher behind DE Kabeer Gbaja-Biamila, and he would take the roster spot of DE Jason Hunter.