When you click the bump link on someone else's question, it gets taken to the top of the "recently bumped" list under the New and Interesting menu at the upper left of your screen. If it gets enough bumps, it will get to the top of the "most bumped" list. Meanwhile, you get points for bumping and the person who asked gets points for it being bumped, which eventually unlock other options that aren't available until you level up.
at 9:33 PM on Jun. 4, 2011