I will follow and expand upon Jason's topic.
Fastest/Most Famous you've beaten in a race
NCAA D-III West Regional Championships - 11/12/2005
Bush Park, Salem, OR
16 Silverman, Peter Chapman University 26:09.50
17 Symmonds, Nick Willamette 26:13.85 15
Symmonds: NCAA D3 Champ and US Indoor Champ, PRs: 800m - 1:44.54 (2007); mile - 3:56.72i (2007); 1,500m - 3:40.91 (2006)
Granted an 8K is 10 times his normal race length and he was probably just taking it easy to help his team qualify, but a win is a win.