From SFBC:
Celebrate San Francisco's biggest day of bicycling at the SF Bicycle Coalition's big Bike from Work Party with DJs, a photo booth, fabulous raffle prizes, snacks hosted by Whole Foods and complimentary bicycle valet. $5 for SF Bicycle Coalition members, $10 for non-members, or join at the door and get in free. 21+. For more details see sfbike.org/btwd.