In fact, there are many visitor maps out there. However, since this stuff doesn't require much technical expertise, the ones that are average in quality also aren't very attractive. For example, the earlier Bravenet and ClustrMap, and later Frappr.com - while there was some improvement in design, their loading speed is just too slow!
Later, I discovered MapLoco. Even though it's quite simple, it's indeed more refined.
Here is my MapLoco:
Visitor Map
Now, try making one yourself!