Xnapper - Take beautiful screenshots instantly
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Pika.style - A free tool to quickly convert screenshots into beautiful website and device mockups. You can create customizable images for App Store, Instagram, and more
Shutter - Shutter is a feature-rich screenshot program.
Screely - Screely instantly generates dribbble-ready images. Simply upload your screenshot and we'll do the rest.
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