There are some great articles and resources out there on the interweb about using font stacks in your CSS to ensure your site has the best chance of working well and looking as it's intended to on any combination of browser and operating system / device you can throw at it.
However, a site I worked on recently used the font all designers love to hate: Comic Sans. Almost all of the advice I could find about this font went along the lines of "it's rubbish - don't use it" (that's the polite version, obviously).
