I couldn’t find any real simple method of backing-up minecraft saves, so I made my own:
set worldFolder=World1 rem The name of the world to be saved. set rarFileName=World1Backup rem The name of the backed-up world. call "C:\Program Files\WinRAR\Rar.exe" a -ep1 "%userprofile%\Documents\My Dropbox\%rarFileName%.rar" "%userprofile%\AppData\Roaming\.minecraft\saves\%worldFolder%"
Copy it into notepad, edit as necessary, save it as a .bat file and run! Nothing fancy here, just rar’s it up and saves it to the root of your dropbox folder, overwriting any previous backup.