Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
UI Movement - The best UI design inspiration, daily
Shutter - Shutter is a feature-rich screenshot program.
UI8 - Carefully crafted UI design assets
Snipping Tool - Use Snipping Tool to capture a screen shot, or snip, of any object on your screen, and then annotate, save, or share the image
UI Garage - Specific mobile and web design patterns for your inspiration