Typophile is running an interesting collaborative experiment in which users collectively participate in building a bitmap font by choosing one bit at a time, black or white. The Smaller Picture
At first I thought that it would only be a matter of time before the letters and numbers were formed albeit, slightly deformed. However, this is assuming that the group all share the same goal. If a significant percentage or participants have the goal of not creating a readable font, the project will never succeed.
I also noticed that there are measures in place to prevent you from trying to manipulate a single glyph. The system keeps track and only allows so many alterations over a given period. I assume clearing your cookies would defeat this though.