The #1 way to present your website on the #1 mobile device.
While websites look great on iPhone, they're not made specifically for it, so the typical website will be far less user-friendly than an iPhone application. iPhone web apps are a great way to browse existing websites as if they were native iPhone apps. The following are a few such apps I've created for others:
AP Mobile News Network
Runner-up in the Apple Design Awards 2008.
I Can Has cheezburger
Touch your daily lolcats 'n' funnies. WANT.
Moguitars.com Guitar Tuner
Tune your guitar to pitch perfection anywhere.
Modguitars.com Guitar Chords
A super-fast chord library right in your pocket.
Remember, to use any of these great apps, just visit their websites on your iPhone!