Alternate reality gaming in Second Life, or Andy Havens and I share a brainwave: how about publishing some ARG content in Second Life?
On one level, consider SL to be yet another venue for pushing or finding content, like the Web, email messages, phone calls, etc. On another level, SL is a venue for hosting ARG communications, as part of the set email/discussion forum/Web page/IRC/phone/etc.
Using SL to access traditional forms of ARG content, like Web pages, isn't that interesting on the face of it. But it might be a nice reward to find ARG content from a surprising place, like a tv screen showing a video clip, revealed on a certain spot of a specific wall.
What ARG implementations would maximize SL's attributes? Emotional bandwidth is a key selling point, according to the Lindenii, so interaction with an avatar could be powerful. This applies to characters and other players. Virtual environments, socially experienced, would make for fine clue-hunting grounds.
How about altering the SL experience? We could imagine a version of theiLoveBees HTML source code weirdness in, say, the recent grey goo attacks. This does lead to classic ARG ethical questions, a la the Wikipedia content editing topic.
Lag might be a problem, since it makes publishing some content uneven. Will we be misled in trying to read text on an object or avatar, looking for clues, when the text is only the result of a rendering error?
A related potential problem: the difficulty in exporting content from SL. This is in part a preservation issue, one which the ARG world needs to solve - i.e., what happens to our virtual spaces if SL goes dark?