Good Vibrations has a great deal through Yelp for their in-store customers: Get a $20 gift certificate for only $10! This deal is for in-store purchases only and is good for one year from the date of purchase. Good Vibrations has stores in San Francisco, Berkeley, and Boston. If you’re interested in this deal, then you might want to purchase a gift certificate ASAP because I don’t know when this deal ends. Make sure you buy the gift certificate through the correct Yelp page–you don’t buy want to buy a gift certificate to their San Francisco store if you plan on redeeming it in Boston!
Good Vibrations Magazine has links to to the Yelp Pages/deals for each store.