Basically the web has taken that model and made it much easier to disseminate, but the current ARGs that have been appearing over the past few year have been operating on huge budgets and large amounts of resources. The Audi Art of the Heist game actually parked a car somewhere at the Coachella music festival in California that game players were actually supposed to "break in to" and steal an SD card that contained further clues. Although Audi forgot to leave the doors open, and no one got the card. Oops.
Mind Candy's enormous ARG Perplex City has really taken things to an extreme. Their game has been running for the past three years, and recently one of the "historical objects" (the Receda Cube) that gamers try to find through puzzles, clues, and cards was found, and netted the player $200,000 (that's real money, too) in the process. The game designers stage car chases, have black helicopters buzz people, and can generally scare the bejeezus out of you. Not too shabby for gaming.
Although most ARGs tend to be tied to something that they are promoting (Halo 2, Audi, A.I., Perplex City sells "game cards" that you have to purchase), some are starting to appear that have a purpose other than driving a product or a brand. Recently announced at GDC was Jane McGonigal's socially conscious A World Without Oil ARG that asks users to imagine how they would function in a world without gasoline or oil.
Both aspects of ARGs have the same goal, they want to harness the community aspect of the ARG to do something, whether it's educate, get a message across, or sell a product. It taps into Linda Stone's theory of "continuous partial attention," meaning that you'll keep coming back into the game day after day (possibly hour after hour) to check on things, and see if the game has advanced, or if anyone has figured out the riddles. It's almost like incessantly checking your email, just in case you might have missed something in the past few minutes.
Check out some of the ARGs out there right now, including the panelists' own ReGenesis, and the fairly amazing Perplex City. With more on the way (including a mystery "socially responsible ARG from panelist Brooke Thompson) we'll be excited to see what comes our way, alternatively. Plus we really feel like pirates now after typing ARG so many times.
ARGnet - the Alternate Reality Gaming network
Unfiction - all about Alternate Reality Gaming