About a week ago I started using Dropbox to sync files between multiple computers at work and at home.
DropBox is a great way to manage multiple media centers. For someone like me, who runs Windows Media Center on 3 computers, making sure the latest files for Media Browser etc are running on all three computers is a pain.
DropBox does function alot like a shared drive on a server. The program becomes even more useful if you do not have a home server or network drive. It is your own personal file repository. You would just download any file you need for your media centers to your Dropbox and then access those files from every computer on your network.
The first 2 GB are free when using Dropbox. That size should easily handle all of your potential media center related files like Media Browser, Shark Codecs, or an remote control app you want running in the background.