Sat Nav tour guides

AFAIK you can navigate to things like "points of interest" on current satellite navigation toys, which is nice, but how about a full on tour guide:

"on your left you will see the cafe where Last of the summer wine was filmed ...... turn right now .... and now you can see where Compo crashed his bicycle in episode 12.... turn left after 1 mile ...." and so on.

I guess the scenarios are:
- You want to go on a tour, or follow a plan route (say monte carlo F1 circuit)
- You going somewhere, but want interesting bits mentioned to you
- You want to drive to an exciting/fun road with no speed camera

Surely that kinda information can be put on a DVD or memory card and sold at £10 a pop?

Even better would be SatNav that updates its self via Wifi/bluetooth when you car is parked at home, then you could buy updates and guides online too. And if you have a "temporary" net connection you could also add extra search parameters to your navigation too, for example, "I want a fun road where the weather is sunny and there are no roadworks, no caravan sites and no motorbike events nearby".

Might be a nice way to introduce a new business model from a gadget that's currently a one off payment and then end of customer relationship until upgrade time (unless its a built in jobby then you can't upgrade the gadget, just the information).