This example demonstrates an interface (using javascript and google maps) to "discover" points relevant to you on a map.
Instructions:
Click on the map to create the vertices of a polygon outline around the predefined green markers on the map. Make sure to fully complete the polygon by joining your lines back to the start point.
The popup dialog should then reflect the markers you've surrounded.
Pressing the "Clear Route" button removes the polygon outline so you can start again.