There are plenty of great co-working spaces in San Francisco and Silicon Valley. Here’s a list of the top ones:

Founders Space
https://www.foundersspace.com/coworking/

Spaces
spacesworks.com

SOMAcentral
http://somacentral.com/

Galvanize
http://www.galvanize.com/

Impact Hub
http://www.sanfrancisco.impacthub.net/

Werqwise
https://werqwise.com/

Sandbox Suites
http://www.sandboxsuites.com/

Taqueria Trabajo
http://www.taqueriatrabajo.com/

Makeshift Society
http://www.makeshiftsociety.com/

Spherepad
http://www.spherepad.co/

Shared
http://www.shared-sf.com/

Workshop Cafe
http://www.workshopcafe.com/

Co-Spot
http://www.co-spot.com/

The Vault
https://thevault.co/

RocketSpace
http://www.rocketspace.com/

Nomad-a-What
http://www.nomadawhat.com/

ConnectionsSF
http://www.connectionssf.com/

Invention Hub
http://www.inventionhub.co/

Center for New Music
http://www.centerfornewmusic.com/

DG717
http://www.dg717.com/

Parisoma
http://www.parisoma.com/

BeSpoke
http://www.bespokesf.co/

WeWork
http://www.wework.com