Thum.io - A real-time website screenshot generator
Scrola - Create scrolling website screenshots, easily
Screenshot Tracker - Capture and keep track of full-sized web page screenshots
Screenshot Bin - Generate website screenshots and thumbnails at scale, right from your app. Screenshots as a service.
Microlink screenshot - Take a screenshot of any website
Full Page Screen Capture - I built a Chrome Extension that allows you to save a screenshot of an entire webpage as an image