High Dynamic Range. Basically its taking 3 or more exposures at: normal exposure, 2 stops under exposed, 2 stops over exposed. Then the three photos are combined together to give you a photograph with highlight, shadows, and mid range. Then people tend to tone map the result.
http://www.flickr.com/photos/lynchburgvirginia/
If taking three photos you need a tripod. But you can have software create the three exposures. Most use photomatrix.