I love it when designers create applications, rather than an applications developer hiring a designer to polish up the pixels. What you end up with is not just some pretty buttons and animations, but an intelligent interface built from the ground up. The Feed is a fantastic RSS reader for the iPad, built by Ocean Observations, primarily a design agency (although the only person I know from that team is Max Rudberg, the jailbreak theme guy).

http://beautifulpixels.com/ipad/the-feed/