You think that your PC is cheaper than my Mac? Yes?
Well, check out the price list for upgrading your OS to the latest and greatest bug-ridden, Swiss-cheese securitied offering from Redmond. Someone accidentally put it on the web.
Order now from Amazon.com
Microsoft Windows Vista Home Premium $239 full / $159 upgrade
Microsoft Windows Vista Ultimate $399 full / $259 upgrade
(Both qualify for free shipping ;^)
By way of comparison, the Mac OS is included in the price of the computer, is easily transferrable, and the typical upgrade price is $129.