I have been looking for nice clubs in London to go to and noticed that some clubs used the potential of Facebook to market themselves. As Facebook has more than 100 million users...it is not a bad idea!
The Q Bar has a Facebook groups that offers you special promotions and makes you feel as a VIP if you join their group. So does the Strawberry Moons which even has "Facebook" in their menu along side "The Venue" and "Gallery". Smart!