It doesn't seem to work for me. Some error about there being no map, as it was registered for being used with a different site.
It might be fun if you suddenly "appear" from beneath the surface in <insert place I would be if the google map worked>, with a shovel and helmet with a lamp on. Unfortunately physics defies us, so maybe we could dig through the moon instead - although
some people* claimed it was man-made and hollow, hence the reason the gravity is so much weaker there than it should be. It'd therefore be much easier to dig through there.
*
Others also claim the moon was made by aliens to protect the Earth from things in outer space, causing tides to help life evolve, and so on.
(
Some of the others have slightly more reliable-looking sites than that one, if not by much).