I am standing in the middle of Central Park, and other than my guide, Satchmo Prototype, no one else is around for miles. A week from now, this place will be teeming with humans and zombies. But I’m not worried; this isn’t real life — it’s Second Life, a wildly popular online universe launched in June 2003 by Linden Lab. Second Life (secondlife.com) is a 3-D world created entirely by its members, or “residents.” Free to download and use, it’s not a game exactly. It’s simply a place to meet, chat, explore, and fly around (yes, the laws of gravity are optional).

In real life, Satchmo Prototype is actually Chris Carella, chief creative officer of the Electric Sheep Company, the world’s largest firm dedicated to building 3-D environments for online worlds. They’ve built a replica of Yankee Stadium, a Ben & Jerry’s Museum, and even a giant vending machine that sells virtual Nissans. This version of Central Park is part of a game promoting the Will Smith movie I Am Legend. “This whole project is set in a futuristic dystopian New York City where humans are turned into zombies and others are trying to find a cure,” says Carella of the game within Second Life that follows the movie’s plot, pitting zombies against humans.

If you think exploring an alternate online world is a waste of time, consider this: time is money. In the 24 hours before my visit, Second Life residents spent $1,726,361. Of course, as an alternate reality, Second Life has its own currency — the Linden dollar, available for purchase (with real money) on LindeX. And companies and entrepreneurial programmers from across the globe — including AOL, IBM, and Reebok — are flocking to Second Life to pocket as many Lindens as they can.

US$250,000 — Average traded per day on LindeX
L$270 — $270 Linden dollars, equivalent to one U.S. dollar
50,000 — Number of people who are making a profit with Second Life
US$50,000 — Amount the area called Amsterdam recently sold for, believed to be the most expensive Second Life transaction to date
8,548,178 — Population of Second Life as of July 2007
$1.5 million — Average daily economic activity in second life in April 2007
20% — Chance that civilization as we know it is actually a computer simulation, according to Dr. Nick Bostrom of Oxford University
80% — Projected number of active Internet users who will have a Second Life by 2011, according to Gartner Research

Want to get a taste for what Second Life is capable of? Visit these real-world locations painstakingly reproduced online.
> Yankee Stadium: You don’t need a ticket to see the House That Ruth Built. This model of the Yankees’ home field will give fans baseball fever all year round.
> The Louvre: With sculptures on the first floor and paintings and drawings on the second, the Second Louvre doesn’t compete with the depth of the real thing, but its halls are worth a gander.
> Starry Night: Sure, this doesn’t exist in reality, but resident Robbie Dingo created an area of Second Life to replicate the classic Van Gogh painting. Its rich color and attention to detail really pull you in.

> Avatar: An online graphic representation of oneself.
> Camping: Second Life residents can earn Linden dollars from “land owners” by sitting in their space for a period of time.
> LindeX: Linden Lab’s online currency exchange for buying Linden dollars.
> N00b: If you’re reading this and are confused, it’s likely you. (It’s shorthand for “newbie.”)
> Poseball: A ball that causes an avatar to perform a programmed action, like dance a tango or play air guitar.
> RL: Real life, or as the Linden folks call it, 1st Life.
> Teleporting: The favored mode of transportation in Second Life.