Be sure to block Myspace if you haven't already. Instead of my usual 20-30 cent clicks, I had 15 clicks paying out less than 20 cents total, then visited my site and saw some idiot's personal Myspace page showing up in every ad unit. I really can't believe how there's no screening process for these things. Now that I blocked the domain, everything's back to normal.
if it ads about those personal myspace then it doesn't mater what niche your website is. I'd say if you still have space left on you comp ads then use one for this