For those of you working 7-man mechanics or looking to move up to a conference using 7-man mechanics, there are three different PowerPoint presentations from the NFL in the following thread if you are interested. Many of you may have seen these before, but some of the slides have some very good motion showing where ceratin officials will go based on the play. Another one strictly deals with trips formations.
http://www.refstripes.com/forum/index.php?topic=469.0