During the summer of 2006, myself, Ryan, and Matt traveled from one coast to the other and back in 18 days. We documented what we saw and our experiences, and we streamed that information to the internet. We had a webcam posted on the dash, pointed on us. We had a digital camera mounted to the windshield, pointed outward. This camera took photos every ~30 seconds, which combined into a time lapse movie of our drive. We uploaded all of this data to our travel web site for viewers to consume live over an internet-enabled cell phone. We also took GPS readings of our position every 30 seconds, which we combined with google maps to display our location and speed on the road.
In the 18 days we broadcasted, with word-of-mouth advertising only, we achieved over 2000 unique visitors. It was a unique, wonderfully successful experience, and I would do it again in a heartbeat.
You can review our travel journal and our travel photography of the trip.