If you have download Firefox 3 today, on June 17th 2008, which is also the general public availability launch day of Firefox 3.0 (FF3.0), you’re indeed participating in Firefox 3 Download Day, which attempts to make it to the Guinness World Record as the most downloaded software in a day.
Those who had downloaded the Firefox 3 during the Download Day, which running from 11:16 a.m. PDT (18:16 UTC) on June 17, 2008 to the same time on June 18, 2008, can also download and print the personalized Firefox 3 Download Day certificate from the following URL:
http://www.spreadfirefox.com/en-US/worldrecord/certificate_form (no longer available)
Simply enter your name and a nice look certificate to mark the participation in record breaking FF3 launch in PDF format is yours to download, and print.