Sometimes porting a bit of code to another platform or piece of hardware isn't about the ported code delivering new features to the device. Sure, sometimes it's about opening the device to a specific application, and sometimes it's just about opening the device up to a new development approach. Sometimes the idea is to push the code (and the device) further, to learn -- because you can.
Sometimes these ports don't get all that far. Four years ago I managed to get Linux running on an iPAQ through online tutorials. I've long since sold the hardware, and running Linux meant a command line, and a basic X windows environment. Functional? Not really. Fun? Wouldn't have done it otherwise.
More recently, the 2.6 Linux kernel has been ported, and is running with some basic functionality on the iPhone. The Linux on the iPhone Project says that while this port is a first draft missing many drivers, the kernel boots on first and second generation iPhones and first generation iPod Touches.
