I just stumbled across Grand Canyon GigaView, a blog site documenting an 18-day raft trip down the Colorado River with an extensive collection of gigapan camera views.
The author/photographer is Thomas Hayden who explained how he got started:
I was one of the original producers of the street-level, 360 degree imagery that made it possible. In 2006 and 2007, I drove thousands of miles across America in a VW Beetle with a specialized 360 degree camera on the roof and high-end GPS instrumentation onboard capturing images of everyday locations that captivated the world. My dream has long been to take the idea to the next level and capture immersive imagery of unique locations in the same manner.
Last March, I had my chance to turn this dream into a reality by taking another camera technology, the GigaPan, with me on an 18 day wilderness rafting expedition through the Grand Canyon.
The next step is to return to the Grand Canyon with a 360 degree video camera (as I had for Google Street View) and capture everything.