Smashing Magazine is featuring a nice showcase of websites specifically optimized for iPhone. You'll also find some useful tools and tips to help you optimize your website for the iPhone.
One of my favorites so far is iPhoney.
iPhoney gives you a pixel-accurate web browsing environment—powered by Safari—that you can use when developing web sites for iPhone. It’s a perfect tool to see how your web creations will look on iPhone.
That's Right, HMK
Thanks to the smart folks over at Samshing Magazine.