A financial consultant on Valleywag, a tech gossip rag, believes that Second Life's economy is really just a pyramid scheme.

We concluded that we weren't playing in a market at all. We were suckered in by a classic pyramid scheme, albeit one with a pretty new user interface. New entrants plow real money into the game. Only the guys at the top can extract that money with any volume (and in excess of the risk-free rate of return). Attempts to move anything more than token amounts out of the game generally result in real-returns of almost exactly the prevailing USD deposit interest rate.

(thx, franz)