Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.

Nimbus Screenshot - Take screenshots and record video from your screen

Shutter - Shutter is a feature-rich screenshot program.

Evernote Web Clipper - Clip, don't bookmark. Web Clipper is a browser extension that lets you save any web page, article, or image into Evernote. Download now.

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

ksnip - Ksnip is a Qt based cross-platform screenshot tool that provides many annotation features for your screenshots. - DamirPorobic/ksnip