I tend to move around a lot, and one of my essential software picks is LogMeIn’s Hamachi.

What It Does It Do?

Hamachi works to provide you a virtual private network. You can have   an unlimited number of computers on it, and you can allow each pc on the network to connect via encryption, so it’s great to use if you’re on your laptop at a wireless hotspot. You can share any files over windows filesharing, access shared music via iTunes, collaborate with MS OneNote 2007, send encrypted messages with Hamachi’s built-in messaging protocol, access web servers on connected machines, and more!

In a nutshell, Hamachi allows you to do remotely anything you could do with a PC or server you might otherwise be sitting next to.

Precaution: Hamachi runs as an executable under Windows, and not as a service. Hamachi will only run if the user on any machine you are attempting to access is logged on.

How Much Does It Cost?

Hamachi is Free for a base user license, which works fine for me, and will likely work for you.

Does It Work On Anything Other Than Windows?

Yes! Console versions are available for both Mac OS X and Linux.