There is yet another offer from US Airways for essentially buying US Dividend Miles. US Airways had an offer for their credit card holders for buying & gifting miles that just expired on 29th.
This time you can transfer up to 50000 Dividend Miles and get a 25000 mile bonus. You would need to pay $567.50 (2.27 cents per mile gained) for this privilege. I can see this being a good way to consolidate accounts, and paying 2.27 cents per mile is not horrible if they are used for international business and first class tickets.
This offer is valid for transfers/purchases made from March 1st to March 14th. You need to the this link to access this offer.