I've loved maps since I was a little kid, and there are three fascinating new tools to play with:
Amazon's A9 Yellow Pages service now lets you walk around the neighborhood. They drove GPS-enabled trucks around Manhattan and other cities taking photographs and stashed them all in a database, so when you search for a listing, you see a photo of (some address nearby) the business, and you can "walk" up and down the block. If you search for the Parkside Lounge in Manhttan (where I am playing on Monday night with Kate and Lou) you will see a picture of an intersection, but if you scroll to your left about six images, you'll see this image of the bar. Mondays are bluegrass night at the Parkside, and always worth checking out.
Google is also beta-testing Google Maps which, like everything Google, kicks ass. In particular, the maps are draggable. Try it for directions to Sunny's Bar in Red Hook, where I'll be playing on Saturday night, again with Kate and Lou, and you might actually be able to find the place. Sunny's is worth checking out any Friday or Saturday night.
The New York City map portal features the most detailed maps you'll find anywhere; it not only shows the street location but the actual shape of the building and exactly where it's located. I've been using it frequently since someone posted a note about it to newyorkers a while back. You can overlay locations of subway stations, hospitals, and so on. The only difficulty is that there's no way (that I can find) to bookmark a location.