Gnome Do is a great addition to the Linux Desktop. Although Gnome is in the name it can also be added to KDE and other common environments. One of the great things about GNOME Do is that it offers plugins for improving your desktop so there are many options available to improve you desktop experience.
As stated on the official GNOME DO website:
With a large set of plugins and smart relevance algorithms, Do fine-tunes itself to be the exact tool you need, no matter who you are or how you use your computer. Do can be your music player, your search tool, your file browser, or even your dictionary.
GNOME Do can be installed from the Ubuntu Software Center. Go to Applications -> Ubuntu Software Center and search for GNOME Do.
Once GNOME DO Is installed you can open it by going to Applications -> Accessories -> GNOME DO to start the application.
Once the application starts you should see the dock at the bottom of the page. By right clicking on the GNOME Do Icon you can select preferences and change the settings and add plugins.
The real power of GNOME Do is seen when you type the Super Key+Space (Super Key is normally the Windows Key). Once you hit those buttons start typing and GNOME Do will auto fill based on the text you are typing. If you see the option that you want to run before you are finished typing you can hit enter or tab for more options if they are available. Of course you can also click on the icons to instantly launch the item without typing.
For more information on using GNOME Do you should check out the official page for Using Do at http://do.davebsd.com/wiki/index.php?title=Using_Do
