Brought up several times in our forums and elsewhere over the past few days has been VMware's Gallium3D driver that they use for guest 3D acceleration on their proprietary virtualization platform.
Compared to Oracle's VM VirtualBox graphics acceleration support that is quite slow for OpenGL and often unreliable or the limited attempts at OpenGL QEMU acceleration, VMware has a rather nice acceleration architecture built atop Gallium3D. Using Gallium3D at the heart of their graphics driver implementation across platforms shouldn't be surprising though since they bought out Tungsten Graphics in late 2008 and its these Mesa / Gallium3D drivers now developing VMware's graphics stack.