Image Processing with OpenGL and Shaders | Linux Journal
http://www.linuxjournal.com/content/image-processing-opengl-and-shaders article about image processing on GPU (V4L2 video device, OpenGL 2.0, GLUT or FreeGLUT lib, GLEW lib)
3d
OpenGL Hardware 3D Acceleration for XEN Virtual Machines -- VMGL, H. Andrés Lagar Cavilla
http://www.cs.toronto.edu/~andreslc/xen-gl/ this is a new project from Utoronto. Hopefully it will be usefull in a near fetaure