According to DetroitLions.com, their mini-camp will take place this weekend. The rookies, free-agents and other players will begin arriving on Thursday. We'll get to see Matthew in a Lions uniform for the first time. After seeing him in red and black for the last three years seeing him in blue and silver should be interesting.
Also, nflauctions.nfl.com is auctioning off some items autographed by Matthew. Net proceeds go to the Detroit Lions Charities, a non-profit foundation.
Plus an older video I found on YouTube
Matthew at the Madden Bowl