You run tons of software every day, but how much of it actually lives on your machine? If you use Gmail instead of Eudora or Google Docs instead of Word Perfect, you've heard about "software as service" and "cloud computing". Rather than having a copy of somebody's shrink-wrapped software application running on your desktop machine or even a box back in the server room, you're accessing those types of tools via your web browser or otherwise making things happen across the 'Net.
Firing up a full-blown web browser every time you want to check the mail or edit a document can get to be a bit of a pain. You don't need all of the browser's functionality—or all of its distractions—to get your job done. That's where a tool like Prism comes in.
Running as a standalone desktop app or as a plugin to your web browser, Prism basically creates a single-purpose instance of your web browser. Rather than surfing all around, or getting sucked into Facebook, if you're running Google Docs through Prism, you get Google Docs and nothing else. It's kind of like running Word, inasmuch as you've now got a single-purpose tool that helps you get your work done, and doesn't get in the way in the mean time.
Prism is compatible with systems running Linux, OS X, and Windows as a desktop app, or you can run it as an add-on in Firefox. Either way it's free.