Mine rang once also - however, I read about a scam where people hit call back and it goes to an offshore account that then bills you hundreds of dollars for "services". Basic rule, if was important, the would leave a message.
I just called the number back.. They claimed that I visited one of the affiliated websites and they have a $100 gift card for me. I was supposed to press one to get it. Or Press two to be put on the do no call list.