Billion-dollar deal on a voluntary-pay platform

It should raise some eyebrows that MySQL AB, the Swedish maker of a free database management system, has sold itself to Sun Microsystems at a price that Cnet estimates at (begin Dr. Evil impersonation) one... billion ... dollars. Hopefully it also will open some minds about alternative business models and "low end" innovation.

MySQL's revenue model is best described as "voluntary pay." Anybody can download and use the software at no charge. Businesses are encouraged to sign up for support services, but that's completely optional.

The "voluntary pay" model isn't unique to software; quite a weekly newspapers use it, and some dailies are beginning to experiment with a mix of free and paid circulation that effectively is "voluntary pay" for targeted neighborhoods. It's an intriguing option for a print medium that lets the newspaper control its distribution while continuing to enjoy some of the revenue benefits of the old model.

In the music business, Radiohead stirred things up by offering their latest album as a free "pay what you want, if you want" download. Of course, other music businesses such as Magnatune have long offered unusual pricing models. Magnatune lets you listen online all you want, and pay a price of your own choosing to download files.

And in Kirkland, WA -- the east side of the Seattle area -- there's even a coffeeshop and deli founded by a Google programmer that seems to be surviving on a voluntary-pay basis. The wi-fi is free, too.

The MySQL deal also is significant because MySQL is a perfect example of a low-end disruptive innovation.

You don't have to stir the anthill very much to discover that a lot of highly paid, highly trained Oracle database administrators regard MySQL as junk, a toy, beneath consideration. Blah blah constraints, blah blah referential integrity, blah blah transaction rollback.

But MySQL was "good enough" to create entirely new markers and enable entirely new services, including this blog, which sits atop a MySQL data store. And as MySQL improved, it began displacing expensive solutions in increasingly more mission-critical settings.

Now it's the engine behind Google AdSense, which of course is the revenue engine behind Google itself. Good enough, and then some.