SFist Tonight

FLASH MOB: Ok, folks, it's apparently time for yet another flash mob. This one will last five minutes, and everyone will be singing the Beatles' "With a Little Help From My Friends" (in the key first note Ab). They suggest bringing a walkman or mp3 player to brush up on the song and to bring friends, of course.

6 p.m. // Union Square // free

FOOD: In celebration of World Oceans Day, the Academy of Sciences is partnering with the San Francisco Seafood Alliance to present special culinary events, a panel discussion, and cooking demonstrations on the topic of sustainable seafood practices by local celebrity chefs during the Academy's weekly Nightlife event. There will also be a screening of The End of the Line, a new film about overfishing that received rave reviews at Sundance.

6 p.m. // Academy of Sciences (55 Music Concourse Dr) // $8-10

CRAFTS: Fourteen visual, fashion, and jewelry artists will showcase their wares during Crafty Hour. Spencer-on-the-Go will be set up across the street, graffiti knitting will be in process around the event, and possibly a renegade band will set up in the alley.

5 to 9 p.m. // Bloodhound Lounge (1145 Folsom St) // free