I just found a nice & short article by Laura Tiffany on entrepreneur.com, which introduces the virtual environment Second Life and reflects a bit about the abundant entrepreneurial opportunities present in this new business environment where people spend about 1’000’000 $ per day!
I especially agree on the importance of the following and question Laura poses: “But the bottom line for entrepreneurs is, will Second Life really pan out? Or is it just hype, since the majority of people have never ventured virtually or even heard of it?” Laura at least answers positively: “Your mom may never understand exactly what a 3D world is, or the point of an avatar. But enough other people do that a whole new class of entrepreneurs has been born to serve their needs.”
Linden – Second Life’s producers – also maintain a page listing business opportunities: http://secondlife.com/whatis/businesses.php