Groupon is definitely my favorite group buying site. I think i have bought over 10 vouchers from them (mostly food related). I love dining out and really saved a lot just by availing of the discount offers made available! If you want to try a new place to eat out, just check their deals.
Aside from the food and dining deals, they offer great travel and activities deals. Even if I don’t have enough time, I still make it a point to go to Groupon's site everyday.