I was in a conference so I couldn't answer. The call didn't left a vm so I knew it could not be that important. Googled the number and came up this site to see what everyone else was saying about this number. I added this number to my contact book as Firstname: Don't and Lastname: Answer. That way if they call back, caller ID says Don't Answer. In the notes field of the contact I put today's date. Every time this number calls I put that date in the note field. That way when I check my contact book every 6 months to clean out old numbers I'll know to delete this entry if I haven't received a call from them in 6 months.
An unsolicited robo-call offering a free Wal-Mart gift card. There was no option to have my number removed and it is on the Do Not Call list anyway. Apparently that doesn't mean much.
After several seconds a Recorded voice came on saying "please hold as our menu options have changed" and then started to tell me I may have been selected to receive a $100 Walmart gift card. I hung up.