"Wink is a Tutorial and Presentation creation software, primarily aimed at creating tutorials on how to use software (like a tutor for MS-Word/Excel etc). Using Wink you can capture screenshots, add explanations boxes, buttons, titles etc and generate a highly effective tutorial for your users."
Free online whiteboard and chat that can be easily embedded into your website. Works on any web browser including iPhone, iPad and Android. Use for online tutoring, distance learning, collaborative design sessions or just for fun!