Originally Posted by diburning

In my experience, Shuttle flights and most other flights are priced on distance AND how many seats are left for purchase. If there aren't very many seats left, expect them to jack the price up. For example, PHL-BOS is usually $50 since there are many flights and the elites are spread out, so half or more of the F cabin is up for sale. But, there have been flights that I've been on where there were only 2 seats left, and they were charging $75, presumably because of the (perceived) higher demand of a product they have in shorter supply.