Teampaper Snap - Take a snapshot, highlight key areas and share feedback
ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
Zapsnap - Temporary peer to peer screenshot sharing in your browser
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Envelop - Immersive virtual reality platform for the Windows desktop, use all your Windows apps in VR.
LightShot - The fastest way to take a customizable screenshot.