By using the "three browser trick", you could potentially get 150,000 miles when opening three cards: Amex version, Visa version, and Business version. You need to spend $3,000 within 4 months. In addition to 50,000 miles, you also receive $100 statement credit after your 1st AA purchase within 12 months and a companion certificate (lowest fare does not qualify). And they all come with waivers of 1st year annual fee.
The Amex application page (dead)
The Visa application page (dead)
The Business Visa application page (still alive as of 12/1/2012)
Finally, there is a slightly better offer for Business Visa: you got 50,000 miles after spending $3,000 within 4 months plus $150 credit after your 1st AA purchase within 12 months and two Admirals Club day passes. Another good thing (just to make you feel better) is that the landing page is still working.
The landing page for the better Business Visa offer (redirecting to Citi homepage as of 7/20/12)
The application page for the better Business Visa offer (still alive as of 12/2/2012)