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

Snip&Sketch - Quickly annotate screenshots, photos and other images with your pen, touch, or mouse and save, paste or share with other apps.

Shutter - Shutter is a feature-rich screenshot program.

Picosmos Tools - Picosmos Tools integrates picture browsing, editing, layout, frames, and cosmetic effects into one set. It also provides plenty of source material.

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

Acethinker Screen Grabber - Acethinker Screen Grabber is an amazing screen recording application that allows the users to record the computer screen along with its audio and high-quality videos.