Here's how Microsoft could exploit GPL'd programs for profit. It fits quite neatly into their upcoming .NET strategy, along with the trend towards centralized content control and pay-per-view economic structures.

The key idea here is that a company only needs to release source code of a GPL'd product if it sells the product itself. Conversely, if it permits access to the product without actually selling it, it doesn't need to make available the source code.

All that Microsoft has to do is convince Joe Public that he is better off using a broadband Internet connection and an very advanced proprietary client (Windows XP-like?) to talk to MS's massive servers. There, Microsoft can pinch any number of GPL'd programs and permit access to them while not distributing the programs themselves. The core of the system could even be an adapted X-Windows server which never gets sold. The whole system could then slide back to the IBM mainframe-teletype days and the GPL is subverted by The Man.

Will this work? I'm not sure. But it sure seems to fit with the general move towards centralized control. And they call Linux fans Socialists!