ShrewSoft VPN Client

The Shrew Soft VPN Client is a free IPsec Remote Access VPN Client for both Windows 2000, XP, Vista and Windows 7 operating systems ( x86 and amd64 versions ) and for FreeBSD, NetBSD and Linux based operating systems.

Free Windows Linux BSD

sshuttle

sshuttle: where transparent proxy meets VPN meets ssh sshuttle is the only program that solves the following common case: Your client machine (or router) is Linux, FreeBSD, or MacOS. You have access to a remote network via ssh.

Free Open Source Mac OS X Linux

Cisco AnyConnect

Make the VPN experience simpler and more secure with the enhanced remote access technology of Cisco AnyConnect Secure Mobility Client.

Commercial Mac OS X Windows Linux Android iPhone iPad Blackberry Windows Phone

OpenConnect

A VPN client compatible with Cisco AnyConnect VPN Client (now Cisco AnyConnect Secure Mobility Solution) and an open source substitute for Cisco's official Linux client.

Free Open Source Linux Android BSD

VPNC Front End

Front End to VPNC, a command line VPN client for Cisco VPN hardware. This client is known to work on: Windows 2000, Windows XP, Windows 2003, Windows Vista, Windows 2008...

Free Open Source Windows