YouTube for the road.
When we were on Skye recently, we shot a video from the car, and it's really interesting playing it back. To minimise shake, you need a camcorder with anti-shake correction and film on a wide angle lens (that way you also get more scenery to look at). The single track roads with sheep on them might be an eyeopener to tourists.
Support virtual driver at Cambrian House.
My other top ideas are currently
The Voice Bank
Early stage investor.
Intelligent search spider.
User Comments: "Basically the next google".
Site Quality Report.
The Idea Tree.