This one is cool;
From the site;
Warhammer 40,000 by Games Workshop is the world's most popular science-fiction wargame, but
AT-43 by Rackham is gaining in popularity, also among players who are used to Warhammer 40,000 (or
40K, as it is often known for short). This web page tries to set out some of the more important differences between the two games in an objective manner. It is mainly intended for people who are used to
40K but have recently started playing
AT-43 and so may need a reminder of these differences, as well as for ones who would like to know in what ways
AT-43 differs from
40K before deciding whether or not to start playing
AT-43 as well.
http://at-43.understairs.nl/index.php?cat=Miscellaneous&page=AT-43%20for%2040K%20Players