GetAccept - GetAccept is a Sales tool for electronic signatures and sales document automation.

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

Signaturely - Super simple eSignature software

Shutter - Shutter is a feature-rich screenshot program.

SignEasy for Gmail - Sign documents or collect signatures directly within Gmail

MWSnap - MWSnap is basically a free to use Windows snapping tools that are used for snapping any part of the screen that is currently displaying on the front of all opened programs and windows.