Dropbox - Secret Uses

Dropbox is a service that lets you sync files to different devices, share files, and backup files.  2GB are free with additional 250MB for each friend you refer.

Share Passwords
One of the main ways to use Dropbox is to use it to share files with your friends and colleagues.  Often times you and your friends or colleagues need to sign up for a certain account and you both need the password to this account.  Instead of dangerously emailing the password back and forth to each other, why not use Dropbox along with Truecrypt to keep your passwords safe and shared.  Truecrypt creates an encrypted file that you can then store on Dropbox.

Version Control
Programmers often use version controlled software like CVS, SVN, and Git.  What this software does is lets you revert back to any revision of a file that you want to, compare differences, and save a new version.  Similarly, Dropbox lets you view past version of your saved files.  You can then restore past versions if you want to revert back to a previous version.  Simply right-click on a file in your "Dropbox" folder, then select "Previous Revisions".  It will open a webpage in your browser where you can see all the revisions you have made along with an option to revert to any version.

Use it as Another Hard-drive
As previously stated, Dropbox is a service that lets you sync files to different devices, not necessarily an online storage service like box.com.  This is because files on the server are also on your hard-drive.  However, there is a way to make Dropbox act like Box.com and store the files only on the server.  There are actually 3 ways.

Method 1 - The Unorthodox
To make Dropbox act as an online-storage only you'll need two accounts.  I'll call them your MasterUser account and your MobileUser account.  Store all your files in your MasterUser account.  Your Mobile account will have ZERO of your files.

Lets say you buy the Macbook Air which only has at this time, 128 GB for storage space.  So you want to store as little as you can on this laptop.  Install Dropbox on the Macbook Air and log in with the MobileUser account.

Now comes the tricky part.  Lets say you want to edit a file on your MasterUser account.  What you can do is:

1. open a browser (on any computer)
2. log into Dropbox as MasterUser
3. Share with MobileUser whatever folder/file you want to edit
4. The file should automatically appear in the Macbook Air's Dropbox folder at this time.
5. Edit the file from your Macbook.
6. Once you are done, repeat steps 1-3 except unshare it with MobileUser this time.
7. Now your Macbook doesn't have any remaining files from Dropbox.

Method 2 - The Not Useful Way
Or of course, you can always just sign up for Dropbox and not install it on your computer and always use the web browser to download and upload your files.

Method 3 - The Right Way
The right way to have some files only on the server and some files synced with your computers is through the Advanced Settings.  To get to the Advanced Settings, click on the dropbox icon, click on Preferences,  then go to the Advanced Tab:

Once on the Advanced tab, click on Change Settings for the Selective Sync.  Here you can uncheck folders that you want to sync on this specific computer.  Click on the Advanced button to see subfolders.  Once done, click on the Update button.