How many RBI'ers were in full length films I got two off the top of my head, again lets try and get as many on our own without cheating.
Reggie Jackson - Naked Gun
Roger Clemens - Kingpin
Good idea for a thread, but you may want to look through these threads so some of the veteran dee-neers don't get too much dejavu.
http://forums.dee-nee.com/index.php?board=4;action=display;threadid=1164 (http://forums.dee-nee.com/index.php?board=4;action=display;threadid=1164)
http://forums.dee-nee.com/index.php?board=3;action=display;threadid=559 (http://forums.dee-nee.com/index.php?board=3;action=display;threadid=559)
http://dee-nee.com/rbi/misc.shtml (http://dee-nee.com/rbi/misc.shtml)
Wade Boggs (http://www.imdb.com/title/tt0349193/fullcredits) as "Nick" in Carnival Knowledge, which looks like a real winner to me.
Dave Henderson (http://www.imdb.com/title/tt0195911/) stretching to play "Himself" in Men in Scoring Position, which sounds way to much like gay porn for my liking.
I find it difficult to believe that Alan Trammell (http://www.imdb.com/name/nm0870787/) ever played a Death Match Fighter, although I do remember his appearance on Magnum PI.