A useful tool in my mobile toolbox dropped the beta tag today: Dropbox went live to the public. This excellent file synchronization tool offers 2 GB of storage for free but you can add more for an out-of-pocket cost. Starting next week, a 50 GB account can be yours for $9.95 per month. We’ve used Dropbox extensively through the beta and like the simple client for both Mac and Windows. You can always access your files through the web as well. The program creates a "Dropbox" folder on your device and you simply drop files in it; these are synced up to the Dropbox server and back down to any other supported devices you have registered. There’s a file revision history and support for shared folders, which we’ve found useful for collaboration.