The ability to do this (and not just for China) is one of the primary reasons I'm looking at new VPN router possibilities to replace the venerable-but-stable RV042s that we've been using for years at clients.

I just haven't found anything yet with a good combination of price, capabilities and hardware VPN support - doubling the price we're currently paying would be feasible, quadrupling it when replacing functioning equipment is harder to justify to non-technical users.

A worthwhile resource for folks with Windows (and with some useful links for others): http://www.sans.org/windows-security/2011/10/25/windows-fire...