http://www.contracosta.edu/library/guides/topics.htm
I went to there, and of them, I'm only mildly interested in minimum wage, national debt, overpopulation, and right to die (assisted suicide). I really just don't care about arguing my points in any of these, because it's a waste of time -- no one except my teacher is likely to read it, and even if they did, it's not like my re-search of other people's ideas, facts, and statistics are going to have an impact.
For the past 7 years I've always done my papers on violence in video games and whether or not it has any lasting effects on people (I always argue that they don't, obviously). I'm bored with that topic. And I'm bored with it for the same reason I'll be bored with these topics: it doesn't change anything.
So maybe there's a controversial topic out there that I won't mind arguing for or against, but I want the it to be interesting*, too.
* What's interesting to me is something you're unlikely to know. Just spout out the first topic(s) that comes to your mind.