Dropbox Share is a tool to easily share files using Dropbox. Using it, you can right click any file or folder on your computer (outside of your Dropbox folder), select Scripts > Dropbox Share and as soon as the files/folders are uploaded, the links are copied to the clipboard and you're notified through NotifyOSD. Also, the shared files get an emblem so you know which files you've shared. There's also an Unity version which you can add to the Unity launcher and use drag'n'drop to share files or folders.
A quick notice for those of you who use Dropbox Share (and/or Unity Dropbox Share): some recent Dropbox builds no longer provide a way to get the Dropbox folder automatically and as a work-around, the script checks if the Dropbox folder is in ~/Dropbox and if not, a Zenity window will pop up (only the first time!) asking you to select the Dropbox folder.
So if Dropbox Share stopped working for you, please upgrade to the latest version. The fix was uploaded for all Ubuntu versions supported by Dropbox Share (Karmic, Lucid, Maverick and Natty).
To install Dropbox Share from the main WebUpd8 PPA, use the commands below:
sudo add-apt-repository ppa:nilarimogard/webupd8
sudo apt-get update
sudo apt-get install dropbox-share
To also install Unity Dropbox Share (firstly add the PPA as stated above):
sudo apt-get install unity-dropbox-share
To add Unity Dropbox Share to the launcher, open Nautilus and navigate to /opt/unity-dropbox-share, then drag and drop the Unity Dropbox Share icon to the launcher.
If something is not working right, please let me know in the comments or submit a bug @ Launchpad.
More info: Dropbox Share | Unity Dropbox Share