I went to Edinburgh on the weekend and the iphone was an absolute godsend.
Firstly, to entertain me on the way up, I downloaded series 1 of the sopranos (which I've never seen) and watched it on the train, interspersed with games of flight control which is the best game ever ever ever (105 is my record for anyone else with it). I'll have to try Rev's recommendation of drop 7.
We got off the train and no-one had a fookin clue where we were going, so I simply searched for the hostel in Maps and within 10 seconds we had directions right to the door of the hostel.
Then everytime we required a meal, someone would make a suggestion of what we wanted to eat (japanese, mexican etc) and urban spoon found us a restaurant with directions and a phone number within a couple of seconds.
Then mor emusic andsopranos on the way home. All in all it was a perfect exhibition of the phoine and it didn't let me down (although I did drop it in a drunken stagger and broke one of the speakers )