Seems that no one mentioned another big option - spending lots of money on a credit card that can yield miles.

I pay a decent amount of my business expenses with credit cards. I monitor the current offers to see where I should concentrate my spend. For example, my wife and I each got the BA Visa last year when the 100,000 free mile offer was extended. Spent some money on the card and was able to take advantage of their 2-4-1 redemption after a $30,000 annual spend. Result? Two First Class tickets to Tel Aviv in May.

Last summer we transferred Starwood points that came from our Starwood AMEX spend during a period when there was a 50% bonus on point transfers. Ended up with two FC tickets to Europe on Swiss (magnificent!).

As long as the airlines find profit in the selling of points to credit card companies, these deals will be out there. But it will be pretty depressing when I retire and the flow of points slows to a trickle!