After many months of looking every once in awhile for a good easy to use OpenVPN client for Mac OS X, my search has finally come to an end!
I present to you Viscosity.
It’s easy to use, imports and export configuration files, works on Mac OS X 10.4 Tiger and 10.5 Leopard.
Make sure you give it a try along with something like Untangle with it’s OpenVPN server.
If you don’t know what OpenVPN is, check this article on Wikipedia.