Smallest Fedora box to use as gateway/firewall/VPN

[Alex]

Hi,
I need a gateway for our new office. I'd like it to run Fedora. What
are my options? I'd like to be able to do the following:

- provide VPN back to the main office
  - provide basic masquerading of hosts on inside network
  - be small enough to fit on a shelf. Preferably fanless
  - web-based administration
  - ssh access

We're experienced admins, so a simple interface isn't specifically
necessary, but desired.

It's only for a few remote office workers, so it doesn't have to be
particularly powerful, but should be responsive enough to support
regular ssh and VPN activity.

Thanks,
Alex