Here's another patent application from Apple that has become public, this one filed on November 24, 2004, outlining a "music synchronization arrangement" for a "computing device" that goes beyond the Nike+iPod Sport Kit. It's designed to let the iPod pick out music that plays at the same tempo that your feet hit the ground when exercising, measured by a built-in accelerometer. It also lets you adjust the tempo of the music, and lets you group various songs according to their tempo or "other attributes."
We already know Apple is keenly interested in exercise and iPods, judging from its recent announcement of its partnership with Nike, where magic shoes talk to the iPod, measuring distance and recording performance. Steve Jobs, in his characteristically upbeat manner, mentioned that it's "90% accurate out-of-the-box, which is huge." We're thinking it would be even huge-er if this turned out to be an "iPod SportPhone" with a GPS device inside that was 100% accurate, a music player, and a cellphone—all in one sleek elegant revolutionary incredible Apple-fied package.
iPod Sport coming from Apple soon? [Unwired View] (Thanks, Staska!)