This site gathers several popular monspace programming fonts, and puts them in a randomized bracket anonymously. You choose your favorite in each matchup, then at the end you find out which ones you ranked highest.

(I didn't create this and am not affiliated, I just saw it a while back and I think it's neat.)

Cool "game" where you compare two fonts and pick which one you prefer, until you've narrowed it down to your favorite font.