http://www.techsmith.com/jing/
You get an icon in your tray. You click it and a menu of options pops up. You can capture sections of your screen to make cropped screenshots, screen videos (with and without sound), and there are other options such as saving to clipboard, saving to your computer, and my personal favorite- saving images to the screencast server and then being provided with the URL ready to paste into any chat convos you're having.
You can add text bubbles, arrows, and whatever quick edits right as you capture the image. I take screenshots all the time and it's been really helpful explaining how to do complicated computer shit to my friends if I can record my screen.
Check it out if you're a screenshot whore who's too lazy to open paint, crop paste, save upload.
This basically does --> Select screen portion ---> Capture ---> Upload ----> Link copy and pasted to clipboard. If you have a high upload speed it takes about 2-3 seconds to take, and upload a screenshot.
So yeah, check it out.
Here's some random shit I use it for.
http://screencast.com/t/U2tmM2PZLf
http://screencast.com/t/L0hClE3rz4l
