When modeling, is there a way to have light shine from behind viewport camera? I'm modeling a simple environment and trying to get some sense of what it looks like with textures early on.  Whenever I switch the viewport to either texture or material mode, though, only the meshes that are lit by lights are visible.  This is slowing down my workflow because I have to keep stopping to add more lights to the scene to see what's happening.  All the lights are also cluttering things up and have to be repositioned every time I move meshes around.

(I've also found the Multitexture/Shadless option in the 'n' menu, but that turns off all lighting information.)

Maya has a nice feature where you can switch from viewing the scene with the placed lights to having the scene lit from a single point light positioned behind the viewport camera.  This lets you get a good sense of what things look like with textures and shading without having to place lights through your entire scene.  Does Blender have a similar feature?
You can put the scene lights on a separate layer, turn them of during viewport editing, and then parent a new lamp to the back of the camera. You can turn off the restrict rendering setting for the test lamp in the outliner. 

This works in Blender Internal, but not in Cycles. You could test texture placment in BI, and then render from Cycles. It's possible to create shaders that work cross-engine, you just have to add the specific outputs. The BSDF nodes wouldn't work in BI, but the textures would.