You just install the software on your home computer and write down the ID number assigned to it by TeamViewer and make a note of the password to connect. Next time you need to connect to it from another place, you can use the TeamViewer application on another computer or go to the TeamViewer web site and connect to your home computer easily. No need to worry about IP addresses, ports, firewalls, VPN settings, etc.
TeamViewer is free for personal use and is available for Windows, Mac OS X, and Linux. For business use, the price is also very reasonable. For more info about what you can do with TeamViewer, check this page out.