Per this blog
"Brad related to MMORGs and the fact that people spend a lot of time online and create alternate lives for themselves in these universes. This has created a whole slew of economic opportunities related to avatars, “items” that can be acquired: land, clothes, weapons,... for hard cash. Second Life is one of the most advanced “parallel economies” as highlighted in this recent Business 2.0 piece. Brad mentioned OnLive and Electric Communities, investments Mobius made in '95 and '96, that tried to implement the same concepts and bombed - having spotted an opportunity but being way too early."