Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Zapsnap - Temporary peer to peer screenshot sharing in your browser
ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
LongLiveSS - A clean way of saving screenshots at regular intervals
LightShot - The fastest way to take a customizable screenshot.
Mark And Scribble - Fortify your presentation skill by Mark And Scribble.