I recently came across this website called JustTellMeWhy.It is a site about dichotomies.You can find some really nice topics.You have to vote for your preference and explain the reason.Here are some examples-
McDonald's vs Burger King
GIMP vs Photoshop
The Chicken vs The Egg
Safari 3.0 vs Opera 9.5 vs Firefox 3.0 vs Internet Explorer 8.0
I found the site and the idea pretty interesting.You might like it too.