On the Microsoft stack side, everyone knows about Visual Studio. The licensing cost for the Team Suite is $10,939. LAMP developers just love to point that kind of thing out. But folks, the fact is, that price is not measurable as the equivalent of LAMP freeware. It’s for an enterprise shop that needs very advanced and sophisticated tools for performing every corporate software role in a software development lifecycle.
These arguments are walking tightrope of avoiding the obvious. Installing all of the Microsoft free tools will make the stack cheaper. But as soon as you want to do something even close to challenging you can bet you'd need support and a license for the real tools. Apparently it's the open source crowd that is subjecting the "market" to FUD?