Diigo's Awesome Screenshot for Firefox is a fairly accurate description of this free extension for Mozilla Firefox: it's pretty awesome, as screenshot tools go. With it, you can quickly capture, edit, and monkey with screen captures before you send them to your friends. You can add text, arrows pointing here and there, and other effects while you're still waiting for your "full-featured" graphics tool to load.
Awesome Screenshot installs without requiring Firefox to be restarted, and it has its own Options sheet, though we could configure its updates from the Firefox add-on manager page. Awesome Screenshot's icon resides at the extreme right of Firefox's address bar, with its own menu for capturing the visible screen or the entire window and accessing the Options. Awesome Screenshot's functional options consist of choosing between PNG and JPEG formats for saving captured images and setting hot keys for its two screen capture modes.
But Awesome Screenshot does more than just capture the visible or entire window, of course. We started by capturing an image of our visible desktop, which opened in a new tab in Firefox, but with Awesome Screenshot's toolbar showing. This simple palette contains all the tools you need to do the most essential image-editing jobs, which is to say, the ones you need most often: Crop, Blur, Add Text, and Rectangle and Ellipse selection tools. Our favorite was the Arrow tool, which draws pointing arrows automatically, in any color you choose, simply by clicking one point and dragging the line in the direction you want to point. The Blur tool let us obscure the faces of innocent bystanders, and we could type in captions, smart-alecky comments, and other annotations easily with the text tool and color picker. Better still is the Undo button (see above, "smart-alecky comments"). We could save images conventionally or click Done to open a page for supereasy posting and sharing online, or save images temporarily or permanently at the developer's Web site. Awesome Screenshot makes it easier than ever to clip, doctor, and fire off screen captures; used with caution, we're pretty sure that's a good thing!