Andrew,
Those have come up quite nicely, like something out of a video game.
I have a shot that I've taken (posted on here a while ago) which this reminds me of, like something out of Quake. I'm a bit over doing HDR nowadays, tending to prefer manual blends.
Mitchell, to get this look, you obtain multiple exposures (between 3 and 5, sometimes more) of the same scene at varying exposure lengths (usually something like -2EV, -1EV, 0EV, +1EV, +2EV) and using software (Photomatix or Photoshop's Merge to HDR functionality) you combine the images and then salt and pepper to taste.
Regards,
Humayun