Do you use Google Maps at all? If you do, you need to check out Scribble Maps http://www.scribblemaps.com/#id=oPV2Vq9_N2. This site allows you to draw on the maps and share them with others. You still have your terrain, satellite and hybrid options as well as the regular map view of course. However, in Scribble Maps you have the option of adding a place marker, text, shapes, lines and scribbles on top of your map. Furthermore you draw those shapes in any color and opacity. You also have an eraser tool to erase the things you erroneously place on the map. The site also allows you to create a custom widget, and save it as a KML or GPX file. Accessing the menu allows you to send the map you created to a friend, save the map or load or import an earlier map you created.