I've recently encountered a post on BlenderNation (http://blendernation.com) about HDRI Tools for sIBL in Blender. Though I haven't had the chance to test out the tools provided in that page yet, I refreshed my thoughts on HDRi (High Dynamic Range Imaging/Images) and IBL (Image-based Lighting) inside of Blender, which is a capable tool in this regard. Take note that I didn't use any lamps at all in this scene. All the shadow and lighting information comes from the hdr file which contains most of the illumination instructions.
You can find more some information here:
The HDR images I used on the examples below were from Paul Debevec's light probe image gallery which you can find at http://ict.debevec.org/~debevec/Probes/ and from Open Footage (http://openfootage.net) which offers very large hdr images very suitable for background rendering and scene illumination.
This review also brought up some issues which are as follows:
- blender 2.5's internal raytraced ambient occlusion's samples couldn't be set more than 32
- for higher quality reflections, shading, and lighting, use a higher resolution hdr image
- render time gets very long with high AO samples
I've provided a packed blend file for you to test and play around.
Download the file here > http://www.pasteall.org/blend/5704