I am seeking an online resource (website) where I can measure the
distance between two cities. Something similar to Google Maps, Yahoo
Maps, Mapquest, etc.

Additional Criteria:
1. The cities I am looking to measure are mostly in Central and South
America, so the resoruce must cover those regions and be able to
mesure distances that start in one country and end in another

2. I am looking for actual mileage as if I were in a car (ie NOT "as
the crow files")

3. Ideally, I am looking for a free resource, but will considering
paying for the service if I have to.

4. I don't necessarily need the route between two cities, just want to
know how many miles it is