6. Virtual Private Networks

Many companies use VPNs (virtual private networks) to securely connect home office or travelling users to the home office. VPNs are also a must for wireless access, since the cryptography used to secure wireless networks is flawed, and you can't trust the operators of wireless access points when you travel.

ssh tunnel in windows? PoPToP supports PPTP protocol. poptop.org

http://www.linuxsecurity.com/docs/LDP/VPN-Masquerade-HOWTO.html