Playing with StumbleUpon, I came upon a list of websites that work only with IE. I still occasionally come across websites that only look good in IE, but I was surprised that there are still websites out there that use javascript to check the user agent and spit back unhelpful messages if you are not using IE.
When I noticed an Australian site, I decided to have a look. Sure enough, this site for an electronics firm in northern Queensland checks your browser and unless you are using IE on a Windows machine, you get "Your are not currently supported" (whatever that's supposed to mean), and the (poorly designed) drop-down menu doesn't appear.
When I looked further at this site (after changing my browser to bypass the javascript), it became apparent that there is absolutely nothing in the site that requires IE as the browser or Windows as the platform. The javascript to block non-Windows non-IE browsers appears to have no rationale except to ensure that people who use other platforms or other browsers cannot navigate through this website, i.e. to turn away potential customers.
Pathetic.