Serpent - 7:04 pm on Oct 10, 2006 (gmt 0)

If the 50 domains are to be informational in nature, one option is "subletting" them out to those who might be interested in maintining them. If you can find blogger types who are interested in generating content on your subject, offer them the opportunity to use your sites as their media to do so.

They win because they get free, hosted sites that have every chance of gaining serious traffic and readership.

You win by getting that traffic pointed at your main site through links that you control.