Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Xnapper - Take beautiful screenshots instantly
MWSnap - MWSnap is basically a free to use Windows snapping tools that are used for snapping any part of the screen that is currently displaying on the front of all opened programs and windows.
BrandBird - Brand your Twitter content uniquely
Shutter - Shutter is a feature-rich screenshot program.
Screenzy - A simple screenshot beautifier