(L) [2013/09/05] [tby voxelium] [Faster Incoherent Ray Traversal Using 8-Wide AVX Instruction] Wayback![LINK http://voxelium.wordpress.com/2013/08/14/faster-incoherent-ray-traversal-using-8-wide-avx-instructions/]
Unfortunately the improvement is small compared to SSE, but at least it's consistently faster and easy to implement.