Groupon? Are they still going?
My wife and I had a couple of Groupon vouchers given to us a wedding presents. However, the conditions for redeeming them were so restrictive - 'you will be at this location, on this date, at this time, and will do exactly what we tell you to do whilst you are there etc.' - they were completely useless to us.
When received as a gift I now consider Groupon vouchers a deliberate studied insult, and question the friendship of the person who actually gives them.