TeamViewer is a solution for easy and friendly desktop sharing. You can remote control a partner’s desktop to give online assistance, or you can show your screen to a customer - all without worrying about firewalls, IP addresses and NAT. Teamviewer is an extremely useful tool when needing to access a computer from far away.
Say perhaps you have a less than savvy friend who is in need of computer assistance. You can easily connect directly to their computer using Teamviewer.
Teamveiwer comes in several different versions compatible with multiple operating systems. One version i find particularly useful is the portable version, able to be ran directly from a thumb drive.
Another benefit of Teamviewer is the ability to use the Web Connector, a purely html and flash based version, able to be used from nearly any browser or operating system.
Personally I use Teamviewer in order to have easy, quick access to MY computer when I'm away from home. Say, school for example.
Teamviewer website: http://www.teamviewer.com/en/index.aspx