GeoTagging photos, What's the easiest way to do it with a Canon?

Normally, I post here with products I've tried, but I'm going to try a question. I love the idea of auto-geotagging the photos I take with my Canon Rebel XT. I'd like to do, and a device like this would be PERFECT. But it's for Nikon. Anyone know of an easy, seamless way to do this with a Canon, or my small Pentax Point and shoot. Or both. Ideas? Email me or comment below.

GPS: Nikon GP-1 SLR GPS Now Available for $240