good day,

you might want to try http://www.itasoftware.com/

you do have to enter a destination at this website, but they allow you to select airports within a certain area as your origin or destination - i.e., you can specify departing from phl (within x number of miles) going to mem (within x number of miles). then it lists all the flights from lowest to highest.

as far as mileage runs, i think they only allow 4 segments.

last, but not least, the fares they provide do not include "web special/only fares."

hope this helps.