Hide Firefox Referals From Firefox Users

I'm glad Julian Bez pointed out we don't have to bother Firefox users with Adsense Firefox referals. Just yesterday, Google opened up Firefox referals for International content providers. I immediately added the banner to the Tools page of this site, and to Free Horoscope Daily, but I totally didn't think about showing Firefox users something different. Julian also outlines how to accomplish this easily with PHP. Thanks, Julian.