Blender Guru - Did you know that Cycles now allows for IES lighting? Download the add-on by Lockal here: http://blenderartists.org/forum/showthread.php?276063-IES-Lamps-to-Cycles It's great for realistic architectural lighting! | Facebook
Using IES lights with Blender Cycles - Blender 3D Architect | Blender 3d, Blender, Blender tutorial
IES Lighting in Blender | Blender Render Farm | Blendergrid