Google recently announced My Maps, a new feature that makes it quick and easy to create your own custom Google Maps just by pointing and clicking. You can add place marks, draw lines and shapes, and embed text, photos and videos, all using a simple drag and drop interface. Your map automatically gets a permanent URL that you can share with your friends and family, or you can publish your map for inclusion in Google Maps search results.

I laughed at the Monster Sightings, but the The Googleplex photo tour is probably a better demo of what can be done.

More info at Google Blogoscoped