LoL, I like GreenThumb, I can't ignore him! No fair, I was getting set up, you beat me to it. Funny thing is, when that post was there I was getting the dreaded googlewhatever script trying to run. Oh, and Chrome should either display Base64 or (in the case of an invalid string) ignore it. Dunno why it crashed the page. Stoopid computers.
My guess would be a large inline image exploit. That's the reason I've seen it done in the past. But I don't work for free so I'm sure the guys that run this forum will be in to fix it all. Me personally I've got the problem child on ignore and it couldn't have gotten through to me anyway. Just tossing out a warning.