A couple months ago, CIO had a great article on open source models: Free Code for Sale: The New Business of Open Source. The really nice part about this article is not that the content is especially deep (it isn't), but that it's a great executive summary of what's going on out there. Having the article show up in CIO also lends real legitimacy to the topic of open source. The article does a good job of descriibing the real business models at work here -- this is more than just hobbyists hacking away on code in their spare hours. I've referenced this article a couple of times already to people who understand the software industry in general, and want to learn more about this aspect of the business.
In search of simple software