Not exactly a website or resource, but I just had to share this video that I just saw on a website. I originally found out about it from a DMX Zone e-mail newsletter I subscribe to, and then found a copy of the video on the DailyMotion website so I could embed the player.
This guy has to have modified the gearing on his bike to get the speeds he was going. Maybe somebody that cycles regularly could let me know if some racing bikes could allow that type of, what appears to be, significant top speed.