In order to back up what we said when we took browsers to task, we needed test cases.  This not only gave the CSS1 Test Suite a place of importance, but also the tests the WaSP’s CSS Action Committee (aka the CSS Samurai) devised.  The most famous of these is the first CSS Acid Test, which was added to the CSS1 Test Suite and was even used as an Easter egg in Internet Explorer 5 for Macintosh.