This is a cool video from Bell Labs (1968) that explains the basics on how computer works and whether they can think of not. Forty years later we can see how the principles apply, the challenges are the same - but a lot of progress has been made on all these fronts. Very well made.
As an answer to those "There's a map for that" commercials, Apple and AT&T have put this ads out. The thing is, Verizon's 3G coverage is better than AT&T's, but Verizon's 3G network technology is slower and technically inferior than AT&T's. As the ads point out, on you Verizon Droid, you cannot be on the phone and use data at the same time. I always use that on my iPhone.