I run my personal site using WordPress, and one reason I like using it so much is that (although this is hardly exclusive to WordPress as a content manager) is all the great plugins available for it. On another site I ran under WordPress, I loved using the WP-Print plugin-- it automatically creates a "printable" version of each page on your site. All of the printer compatibility, none of the actual work.
And now, someone's cooked up an iPhone version of that same plugin, where you simply install the WP plugin on your blog (for WordPress 2.2.1), and instantly you can see all your posts formatted specifically for the iPhone. Instead of creating a whole other, "mobile" version of your site, you can simply put in this plugin, and you can get a link that will reformat your content for the iPhone or iPod touch. Very excellent.
If you run a WordPress blog or site and were thinking about creating a version of it for the iPhone or iPod touch, your work is done. Download the iWPhone plugin from Content.Robot, install it, and you're set.