Potrero Hill Festival/The MAP Potrero Hill Exhibition: The 20th Annual Potrero Hill Festival takes place all weekend. During Saturday's event, Mobile Arts Platform will present visual art, video installations, performances, and spoken word.
Dogtoberfest: Any event involving pets in costumes gets highlighted on SFist. Happening Saturday.
1st Annual Yerba Buena Neighborhood Fair: Live music, acrobats, food, interactive games, kids programs, arts and crafts, and guided art and history walks will take place at the fair on Saturday at Yerba Buena Gardens.
ArtSpan SF Open Studios: It's weekend two of ArtSpan's Open Studios, taking place in the eastern portion of the city.
Longplayer/Long Conversation: On Saturday, for six hours on a 60 foot-wide, custom-built instrument, eighteen musicians and an orchestra of singing bowls will perform musician and artist Jem Finer's musical composition that's intended to play for 1,000 years. Longplayer is in conjunction with (and will interpret) the Long Conversation, "an epic relay of one-to-one conversations among some of the Bay Area's most interesting minds."
Capsule Design Festival: One-hundred thirty independent men's, women's, and kids' clothing and accessories designers, paper makers, glass designers, and other assorted "fantasmigorica" will take over Hayes Valley Park on Sunday.