Cisco VPN Client for Windows

Solution 1:

Shrew Soft VPN client is a free IPSec client that runs on 32-bit and 64-bit Vista.

It does not support existing Cisco VPN profiles (.pcf files) though.

EDIT: Cisco VPN profile import was added in version 2.1.5

Solution 2:

The official Cisco VPN client is free, but you need to have purchased a Cisco service contract with your hardware to download it.

Cisco VPN Client FAQ:

Q. Where can I download the VPN Client software? A. You must log in and possess a valid service contract in order to access the VPN Client software. VPN Client software can be downloaded from the Software Center (registered customers only) . If you do not have a valid service contract associated with your Cisco.com profile you cannot log in and download the VPN Client software.

There is also a program called vpnc, the client primarily for UNIX systems, which runs on Windows with cygwin.

Solution 3:

I think this article summarizes the situation.