Maybe you all know this but I just figured this out. I was trying to use FF pts for a trip on USAir. Great news is that USAir has a bonus mileage promotion. (buy 1 mile get 1 free.) Well, the lowest category wasn't available for a seat (17,500 miles one way-Caribbean) and I looked at the next category. The funny part was that the regular mileage award (30,000 one way-Caribbean) was the same as the mileage needed for a first class ticket(30,000 one way.) I was so surprised and excited. It was a nice bonus to receive the extra bonus miles and also be able to upgrade the flight!! This doesn't seem possible for all flights but it is worthwhile to check your options.