[onezerothrice] has been working hard on creating ARtisan, a flash library for bringing augmented reality to the browser. His goal in creating the library was to make AR projects quicker and easier to develop. The library can provide the location, size, and rotation of multiple markers on screen with little work from the developer. It is licensed under the GPL and comes bundled with Papervision3D, another flash library for manipulating objects in 3 dimensions. He has posted several demos with source and accompanying video.