https://aav4.aavacations.com/special...ionawards2.asp
basically,
<font face="Verdana, Arial, Helvetica, sans-serif" size="2"> After you've selected your vacation, use your accrued miles to pay for it! Just book the reservation, then when you reach the Passenger Information and Payment page, click the button to redeem AAdvantageŽ miles for this vacation, enter your AAdvantageŽ number and Pin number...and follow the screen prompts...combine your miles plus a cash co-payment...</font>
The rate seems to be 500 miles (minimum) = $4.30
and, of course, you loose the 3000 bonus miles for using the site if you use miles instead of cash
[This message has been edited by mashav (edited 12-04-2001).]