Anche questo me lo segno... al momento non mi serve... ma
non si sa mai!
I’ve been using the MS www.foldershare.com for a while and was shown this: http://www.hamachi.cc/ - it allows
you to create your own VPN network that will work from behind any firewall.
Since no inbound connections are required, only outbound it should work from
behind a firewall. The Hamachi application scans the firewall for
ports that allow outbound, and the secure connection is made.
Since there is a Hamachi mediator server on the Internet, NAT isn't an issue because the mediator server negotiates the NAT and port issues. Once that negotiation is complete, the server is out of the picture and two PCs communicate directly.
Now, caveat is Hamachi is potentially a problem for a firewall admin and corporate data policies, but great for people who need anywhere, anytime access. Make sure users are aware that corporate data belongs to the corp, not to the user 
