Skitch
Skitch is a wonderful freeware tool from Plasq helping you creating screenshots with annotations or simple image manipulations like rotation or scaling.
As you can see in the picture, I made a snapshot of my DJ homepage and did some simple things like text and shapes.
You can resize just by dragging or make snapshots even from your connected webcam. You have plenty of customizable settings and a history to see what images you have created.
Another cool thing is a time delayed screenshot as you can do with the Grab tool from the Application Utilities.
Skitch enables you to upload the visible picture to your own FTP server or many other preconfigured image hosters like Flickr or Plasq itself, where you can share it with the world or your friends.
On the bottom of the window is a puller where you can just drag and drop it on to the desktop, a folder or any other dragable application. The file is then named as specified in the textfield and created on your destination with the selected image file format.
There are many other features which would explode this article. Just have look at Plasq‘s valueable demo video. I am sure, after watching you will download, install and love it. Maybe that is the reason why they took a heart as logo.