OpenGL apps running inside a VM use VMGL to obtain graphics hardware acceleration. VMGL supports VMware, Xen PV and HVM, qemu, and KVM VMs; X11-based OS such as Linux, FreeBSD and OpenSolaris; and ATI, Nvidia and Intel GPUs.
Note: latest file in this collection is dated 20/02/2007. There has probably been progress in support of hardware acceleration in Linux virtual machines since then. A detailed Web article found in 2008 that VMGL could be made to work, but was a lot more difficult to implement than the project suggested. (dedoimedo.com/computers/virtualization-3d-support-vmgl.html) Have allocated 3 stars randomly for design and support, as apparently required to submit review - I haven't used this.
This project need more people