Ubiquity is an experimental Firefox plugin designed to give you access to information very quickly... using the command line. What you loose in discoverability, you gain in speed, and for common tasks, it makes a lot of sense. It only works with Firefox right now: once the plugin is installed, Ctrl-Space (Alt-Space on the Mac -- or any key combination you choose: just type help to change the Ubiquity access keys) brings an overlay window in your browser where you can type commands and get results. That's your semantic interface to the web! While the current version is still far from a full-blown NLP platform it's still extremely useful in it's current form once you learn the limited grammar. But even this limitation could disappear once they release the next parser which is very promising.

Searching for John Galt is as simple as typing "g who is john galt". Doing a calculation using the Google engine just requires typing "gc 150 eur in usd" for example. Even simpler, you can select any text on the page and type the one or two letter shortcut for the command. If you read a page in a language that you don't master, just select a sentence in the page, bring the prompt and type "tr this to en" to instantly get the English translation. Other useful built-in commands are the ability to select some content on the page and email it using Gmail. Or selecting a group of addresses and map them using Google Maps. Or even check your Google calendar with a couple of keystrokes.

But the real power of the tool resides in its extensibility. Anyone can write a command with just a few lines of javascript. And even if you don't want to venture there, you can take advantage of those commands written by the more adventurous. I have added 3 extra commands for example that I use all the time. The first one is Text2Link that allows you to transform any web address into a hyperlink. How many times do you see those addresses which are cold and you have to copy the link, create a new tab and paste the url there? Not anymore. Just double-click to select the address, bring in the command prompt and type "te"! The next one is Share-on-Reader that allows me in a couple of clicks to select content on the web and post it to Google Reader for either later review or publishing. And the last one is Thesaurus which funnily enough is not built-in.

There is an increasing number of user-written commands and you can find them all on the Mozilla website. So if you  keyboard is itching and it's becoming jealous of your mouse, head down to the Ubiquitous website and start typing away!