Now that's a business model...

Liquidnet--'Napster for stocks'New York Times

Meet what one money manager calls "Napster for stocks." Like Napster, which shook up the music industry with its file-sharing network, Liquidnet has pioneered an electronic marketplace that allows institutional investors to trade large blocks of stock anonymously. In a sign of how valuable such electronic trading power is, Liquidnet, which began operations in 2001, has just completed a financing deal that values the privately held company at $1.8 billion, according to a person close to the transaction