Google Maps Street View
Wow, the new Street View in Google Maps is quite impressive! They've literally taken 360 degrees pictures of some cities (Las Vegas, New York, and more...) at street level (not the overhead satellite shots) and stuck them together so you can almost see exactly what it's like to be there. You can use your arrows keys and kind of "walk" up and down the street and look around you...very cool. Check out Times Square here.