+1 to AMEX starwood preferred guest (SPG)
By moving SPG point to an airline in buckets of 20000 you get 1.25 miles per dollar (except on United and Continental). If you move point to ANA then you can get some really nice deals to Europe. ANA has different award prices depending on the length of you trip and they often come out much cheaper than the standard carriers. And they partner with Virgin Atlantic (and you pay less in fees to ANA than with Virgin)
This year my SPG points are going to fancy hotels in Europe at roughly 3-5 cent per point.