RB Marion Barber III has been shown the door by the Cowboys, along with trade-bust WR Roy Williams.

Other notable salary-cap casualties include: LB Nick Barnett from the Green Bay Packers; C Shaun O’Hara and G Rich Seubert from the New York Giants (two of the players involved in this play that ESPN celebrated today) — and, shockingly, not versatile but brittle OL Shawn Andrews, due to make $7.5 million this year; DT Jimmy Kennedy from the Minnesota Vikings — with WR Bernard Berrian likely to follow; DT Kelly Gregg, TE Todd Heap, WR Derrick Mason, and RB Willis McGahee from the Baltimore Ravens; and any minute now, QB Vince Young from the Titans.

In other player-movement news, Vikings sometime-starting QB Tarvaris Jackson has signed with the Seahawks — likely closing the door on Matt Hasselbeck’s return to Seattle, though the veteran will surely find a home in Tennessee or Arizona.

Pats OL Logan Mankins and Chargers WR Vincent Jackson are prepared to sign their $10 million tender offers.

And in the feel-good story of the day (particularly if you’re a Giants fan), undrafted rookie free agent — and cancer survivor — LB Mark Herzlich from Boston College has signed with Big Blue.