While certain fonts may be harder to read, researchers at Princeton and Indiana University have found that they may, in fact, improve your ability to remember facts.
In a study of 200 students, they discovered that making things harder to read — whether that meant using fonts like Comic Sans and Bodoni MT or using bad photocopies — actually increased test scores, without any complaints from the students. They believe that if something is hard to read, it engages different parts of our brain, thus making us able to recall that information better later on.
It's an interesting idea, and while still in the early stages, it presents some interesting ideas for note-taking. Maybe we shouldn't be banning Comic Sans after all — next time, try taking your notes in a slightly more complicated font and see if it helps your memory.