Open Source companies with offices in San Francisco?

I'll be meeting next week with the Mayor's office here in San Francisco to
discuss municipal adoption of free and open source software.  I'd like to
collect a list of all companies (or independent contractors) who we would
consider a part of the "free software business" community, with offices in
San Francisco, and ideally with a sense for the number of employees at
those locations.  I know Sun and IBM have offices in SF, and Red Hat at
least used to, Covalent is hq'd there, etc.  CollabNet used to be but we
fled when rents skyrocketed.  Who else?  If you've got a hunch, and
ideally numbers (that I'll keep private if desired), it would be
appreciated.  Thanks.

I'll be using the Largo and Munich examples, but if someone knows of other
good municipal examples (especially if you're aware of any cross-municipal
projects, e.g. an open source project for software used by food banks or
libraries or schools) that would be deeply appreciated.  It's a short
meeting so we don't need overwhelming evidence, just enough to know they
aren't the only ones who'd be giving this a try.

Thanks.

	Brian