I now value miles by what they would bring on the open market. Some may find it hard to believe but there's definitely a small segment of people out there that will beat a path to your door for the opportunity to purchase miles - not awards - for at least 3.5 cents/mile. I'm not talking about rubes that just fell off the turnip truck but rather knowledgable and informed people that already know about programs where miles can be purchased/transferred directly via the airline (for example in AA's case via the buyAAmiles/giftAAmiles/shareAAmiles programs) but they still need even more miles and are willing to pay good money for them.