Lots of websites now have mobile versions that optimize their designs for speed and ease-of-use on the iPhone, reducing scripts and designing for the device’s smaller screen. They usually use some sort of browser detection script that loads a different template on the mobile device.
Sahil Lavingia, creator of the Dayta app, has a quick tutorial on how to optimize your website for iPhone in 10 minutes…using only CSS.
I haven’t had a chance to try it out for myself, but it looks fairly simple.