I mentioned recently a small-plane caravan flight along the route (more or less) of Lewis & Clark's trip to the Pacific. The same company, AirJourney.com, is sponsoring a more ambitious trip later this year.
Now, I'm not actually going to do this. Reason 1: I don't have an airplane any more. Reason 2: the landing in Narsarsuaq, Greenland for refueling is one I've heard about many times without ever wanting to attempt myself. (Problem: it's a landing you have to make, given the huge expanses of ocean on either side; the runway has ocean on one side and mountains on the others; the weather is often snowy, foggy, gusty; etc.) Reason 3: you have to wear a survival suit on the long over-water stretches, which makes you uncomfortable in the airplane and probably wouldn't save you in the frozen water anyway. Reason 4: expensive. On the other hand... flying at low altitudes over Europe! Approaching Greenland, Iceland, Scotland from the sky! Landing in Paris! Dreaming about it -- especially on Bastille Day: priceless, as they say.
Narsarsuaq on a nice day (from "Most Dangerous Landing Strips in the World" site).
How it looks at ground level, from this site:
Pilot suiting up for the run to Narsarsuaq in his Cessna 172, from this site: