Minerva is a multiplatform framework that provides a high level language to specify Augmented Reality applications in a very easy way, equivalent to Blender GameEngine. More info, please visit theminervaproject.wordpress.com
IrrAR is a combination of Irrlicht and Augmented Reality to create the most rapid development platform for augmented reality at the moment. IrrAR creates 3D "nodes" out of real lifer markers to let you insert your 3d world into the real world.