Foldit, a game made by two medical researchers in collaboration with some computer scientists and with consultation from some game designers, taps into people's intuition where raw computer processing power isn't enough. Think distributed computing like the Stanford Chemistry Department's Folding@Home, but instead of donating idle CPU cycles to perform scientific research, you play a game that helps researchers understand human pattern recognition.
According to UW associate professor of computer science and engineering Zoran Popovic in Science Daily:
Some people are just able to look at the game and in less than two minutes, get to the top score. They can't even explain what they're doing, but somehow they're able to do it.
One of the most interesting parts is that they've incorporated competition into the game: between gamers playing for a high score, and actual research groups trying to solve problems. I think a lot about how graphic/visual/interaction design could similarly channel human energy in productive ways. There's got to be another example of this somewhere, right?