Recently I've been playing around with creating HDR style images. I'll save the full technical explanation for someone else. In my own simple words for the uninitiated, it's a post processing technique where you combine multiple images of the same scene taken at different exposures. The reason for doing this is that your camera is only capable of "seeing" a certain range of light and colours, you usually tell it which range to use i.e. whether you want an underexposed or overexposed image. Some scenes are too mixed in terms of different light levels, you could expose for the dark areas or the light but perhaps not both. This is where a technique such as HDR comes in handy, allowing you to retain the detail in the shady areas as well as the well lit areas for example.
HDR images can look like they're not photographs, perhaps computer generated, depending on the algorithm used to render the final image. However, in the right hands they can look pretty cool, for example this one from the Flickr HDR Group:
I'm still very much learning, I've been working with these three images:
My best attempt so far is:
I think I've still got some way to go, but it's been fun trying and learning.