The idea is to use A9.com's project of photographing a city using their Block View technology and transpose that to that to a wider array of transportation in order to record the highways and byways for posterity.
Potentially, there is a possibility of partnership with a whole slew of public transport
operations such as National Train (ie Amtrak), Air (ie Delta) and Bus (ie Greyhound). Government could subsidize the project and use it to encourage public transportation in order to reduce green-house emissions.
From an artistic point of view, it would be awesome to see a portrait of the whole continent via train. From a practical point of view... well I'm sure there are practical aspects as well. Ah, here we are: for scientific purposes, the streaming of data could include temperature, barometric pressure and air pollutants (in addition to the obvious usage of a panoramic camera). All the data could be viewed online with minimum delay as the data could be uploaded using the EDGE network (the same one that Blackberries operate on).