Using the Media on a Prim (MOAP) capability to display web pages, including JavaScript (.js) on faces of objects in Second Life and OpenSim, a simple drawing facility can be provided.
Drawingboard – Single User Whiteboard
Drawingboard is a canvas based drawing app that you can be integrated into web pages. Each user sees only their own drawing, its not shared between different users viewing the same whiteboard on a Media on a Prim screen. The source code and examples of using the Drawingboard on web pages can be found at either:
wPaint.js
wPaint.js is another JavaScript based whiteboard web embeddable package. Again it is single user, each users seeing their own drawing… it is available via http://wpaint.websanova.com/