A friend today showed me something really funny on google maps. Search for directions from London to New York. And follow the directions. ( If you are too busy to read it all, check out No 37 in the directions list. )
It got me thinking, may be google can make some money out of those directions as well. They can display adsense ads next to those directions. For eg: Next to directions between two ports, probably they can show ads for a cruise ship company; directions between two airports, they can probably have ads for some airline company, or probably a travel agent who can help u get a ticket. ;o)
I wont be surprised if someone told me that google is already working on it.