A Google map is no longer just a Google map.
You can still search Google Maps to figure out how to get from here to there, but why would you, when you can use it to pinpoint kosher restaurants in Cincinnati, traffic cameras in Dublin, or hot spring spas anywhere in the United States? How about finding coffee shops in Seattle that provide free wireless Internet access? Or would you prefer to locate the McMansion your boss just bought and find how out exactly how much he paid for it?
I think my favorite (for now, anyhow) is A Foodie's-Eye View of San Diego's Best Thai Food.
Here are some other fun ones:
Find a hotdog stand in Chicago - Looking for some "street meat" in Chicago? Check out this Google Map which plots the location of hotdog stands. I just love the names of some of them - Toot's, Huey's, SuperDawg and Weiner's Circle! Based on the number shown on this map, there are sure to be more locations added over time.
How to Make Your Own Transit Map Mash-up
webwalking.com - Plots your jogging or walking route and computes the calories burned.
fboweb.com - Let's you type in a flight number as a Google search to yield a map of where that flight is.
World Earthquakes mashup
Checks San Francisco's BART schedule.
Dig to the Other Side of the World
homepricerecords.com - Puts home sale data onto a Google map.
Cell Phone Reception
ufomaps.com - For sheer silliness, this is a favorite.
lostacotrucks.com - Find the taco trucks in Seattle.
onnyturf.com - New York City subway map overlaying a city map.
pilotyid.com - Kosher food in scores of major American cities.
monster.com - The job posting company now plots listings on a Google map.
phillycrime.org - Overlays Philaladephia crime stats on a Google map. It's sortable so you can find out how many purse snatchings there were in Rittenhouse Square.
Seattle free wireless coffee shops - When you think of Seattle, you think of coffee. Here is a Google Map of places where you can enjoy a cup of it and use free wifi.
Road Sign Math
Via the NY Times and Google Maps Mania