Playing around with a radiosity shader I made. I might include this effect as a setting for people with faster graphics cards. It's quite subtle in the screenshots, but it looks great in motion. Purple berries cast a soft purple glow on stone, lava illuminates anything near it, and the man's skin reflects light as he's climbing, making the walls look somewhat reflective.
<img src="http://dl.dropbox.com/u/1010927/Forumpics/TCradshad.png">