Is there a formula within Quickbase that would calculate the miles from one point to another if the latitude and longitude were supplied for two locations?

>I like the concept of using ...

They are essential the same formulas perhaps with slightly different coefficients. If you wanted to you could evaluate the accuracy of these various formula by running sample points through the formulas and comparing them to the results of an online calculator:

 http://www8.nau.edu/cvm/latlongdist.html