I recently received an e-mail offer from AAdvantage with what it calls a "MegaMiles" promotion in conjunction with Marriott:
To earn up to 50,000 AAdvantage® bonus miles:
Register by March 31, 2015
Stay between February 1 and April 30, 2015
Earn 2,500 bonus miles every other paid stay*, starting with the second stay — up to 50,000 bonus miles
It's nice to see Marriott and American working together again.
(I don't know if this offer is targeted.)