1560 Powell St.
"I worked at a dorm-like building, the press called it the Y Scraper," says Drew Houston, co-founder and CEO of file-sharing site Dropbox. "We'd go to Northstar"
901 Columbus Café
901 Columbus Ave.
"This is where we would interview people and meet with investors," says Trip Adler, co-founder and CEO of social publishing site Scribd
111 Minna Gallery
111 Minna St.
"Anytime we wanted to have a company party or happy hour, this is where we'd have it," says Garrett Camp, co-founder of peer-sourced search engine StumbleUpon
Ritual Coffee Roasters
1050 Howard St.
"Having the hustle and bustle of this café was pretty infectious," says Jameson Hsu, CEO and co-founder of Flash game network Mochi Media
780 Valencia St.
Café Buon Giorno
550 15th St.
"This outpost—a startup itself— became part of the startup community value system," says Julia Hartz, president and co-founder of ticket-selling site Eventbrite