US Airways is offering a randomized bonus to new members who join by October 15.
They’ll assign the account a bonus randomly, and that bonus will be earned on most account activity in the first 30 days of membership. Within seven days of signup new members get an email letting them know just how rewarding the bonus will be. 80% of signups get a 25% bonus, 15% of signups get a 50% bonus, 4% of signups get a 100% bonus, and 1% of signups get a 200% bonus.
Credit card first use bonuses, hotel points transfers, and mileage purchases don’t count towards the bonus, sadly. But all other activity does. Including, for example, shopping transactions which are also currently earning a 100% bonus.
(Hat tip Keri.)