You make a reservation through their website/app and you get a certain discount off your entire bill including alcohol! No coupon needed, just tell the hostess you made your reservations through Savored/Groupon Reserve.
I used this app all the time at Coco Sala getting 30% off my whole bill. Sadly I don't think they participate anymore.
There are still plenty of other restaurants, a little under 50 participate in the DMV area. Check it out!
Fun Fact: Savored is everywhere, NYC, Miami, LA, Chicago, etc. So save a bit of money while traveling!