Hi,
Draytek (
http://www.draytek.co.uk ) do devices like the Vigor 2950 or 3300 which is a firewall with VPN hosting built in. If partnered with a Vigor 110 modem you can attach it to an ADSL line. I think you can then use one of their other routers for the locations connecting in ti give real network ports with no software needed on the clients.
Cheers,
Paul.
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