You can use [DynDNS][1] to maintain a single, memorable address which is mapped to your IP. Your PC will update the DynDNS website every time it acquires a new lease providing it your routers IP. Then simply set up port forwarding on your router to your PC, and make sure that PC has a DHCP reservation in place from the router so it can always connect.


  [1]: http://www.dyndns.com/