Map Channels is a service that lets you embed a custom map into your website or blog. In addition they have numerous "channels" to look at local events, book hotels and look at street views. They also have a nice function to compare Google Maps with Virtual Earth.
When you get past the flashy "cool" stuff there's actually some very useful functions here. Going to Los Angeles? Need to know what's happening? Below is a map of upcoming events. What's really nice about this is it's actually current to today! Usually these things are months out of date. Oh, and they have your city too. I know because I've checked.
Need a hotel? Here's a map of available hotel rooms in San Jose del Cabo, Mexico. Click a dot and make the reservation!
Here's another cool "channel" - free things to do in London. OK so most of them are parks - I can live with that.
2 years ago