Windows Remote Desktop without a static IP address?
If you are using Windows XP Pro or Vista Business, Enterprise, or Ultimate, you have the ability to remotely connect to your computer without additional software or using services such as GoToMyPC or LogMeIn. All you need is the Remote Desktop (aka RDP) feature built-into your operating system.
Generally, your host computer needs an Internet connection with a static IP address to use Remote Desktop. It is a permanent unique address you can use to connect to your PC from any computer (and some PDA's) with Internet access. But a static IP address from your Internet Service Provider may cost more than the more typical dynamic IP address, and may require installation of new equipment such as a different cable or DSL modem and/or router.
If you want many of the benefits of a static IP address without paying more and swapping equipment, consider the free DynDNS service. Simply create a free account (with user name and password), select a host name in one of the available domains, and download a DNS updater utility to automatically keep your dynamic IP address in sync with your host name. A good set of instructions can be found here.
Remember that if you are using a router between your cable/DSL modem and your computer, you will need to set the router for forward port 3389 (the port used by the RDP service) to your host PC. This should be fairly simple, but you may need to consult the configuration manual for your router.