I think I've found the easiest way of doing this, by using dropbox and symbolic links:

How to sync backed up games using dropbox :

1-Install dropbox on machines you want to use save games with, make sure it is all up and running ok



2-Move your saved game folder (eg. c:\users\username\game name\saves) into your dropbox folder (Dropbox\Saved games\game name\saves)

3-Create a symbolic link from the original save game folder location to your new dropbox saved game location - make sure that the symbolic link folder name is the same as the original folder name
Basically what this will do is create a shortcut, so that when your game looks for its saved game folder, it is actually being redirected to a different location (in this case, the dropbox folder)

Here is a simple app for creating symbolic links: symlinker





Please note: symbolic links only work in Vista and Windows 7 - not XP

Source:
windows 7 - How to backup/sync saved game folders between multiple computers - Super User