This week on “Sick, Sad World”: Web developers who buy Macs so that they can use Virtual PC to test their sites using multiple versions of Internet Explorer. How long has Microsoft known that it’s a huge pain for Web developers to test their sites under IE 4, IE 5, IE 5.5, etc, ad nauseum? I guess you just can’t do that when the browser is actually a deeply integrated part of the operating system. (Yes, I’m guffawing as I type that.)