Wow, that's bizarre. Maybe a bad preference file? Not that I'd really know how to fix that, but that's the only thing I can really think would do this..
That's fracking weird as hell...some of it is actually readable, the letters upside down, backwards or symbols that look like letters, but I can make out "take away your freedom" on the first line.
Something has to be corrupted...probably the font file itself. Unfortunately, I'm not sure what font would be used there, though someone else might. If that's the case, replacing that font file (In /System/Fonts) would probably do the trick.