Don't know whether it was just a wrong number of what.  Some girl called asking if I was John and I said no, it was Hal.  She asked if someone had called about her ad on craigslist and I said sorry, don't know anything about that.  She said someone had called from my number a few minutes ago but didn't leave a message and if I wanted a "good time" she was available.  Since I live alone, and knew no one had called, I just blew it off as a wrong number from a hooker.