Last year Spock posted a link to find sex offenders in your area.
I did a search of Reston, VA. Luckily, there aren't any too near to me. But while looking through the database, I found out that my best friend, who lives in a group house nearby, has a convicted rapist for a housemate!!
The guy's a real jerk, stays out late all the time, and usually comes home drunk.
Fortunately, my friend is buying a house and will be out of there soon!