A bit of humor courtesy of web-heads:
Go to http://maps.google.com/maps
Click on the tab in the upper middle that says “Get directions”
In the first box, type: 1600 Pennsylvania Avenue, Washington, DC
In the second box, type: 10 Downing Street, London, UK
Enjoy the trip! (look at step 24)
(Adapted from a post by Frederick Clegg)