To summarize the thread thus far . . .
For
last-minute award travel, the following carriers charge additional fees (beyond taxes, etc.) for issuing such e-tickets, while the latter do not:
Fees Imposed 
AA, CO, DL (<7 days), US
NO Fees Imposed 
AS (online), NW, WN, UA
[Added CO based on subsequent comments.]
[This message has been edited by SPN Lifer (edited 11-28-2002).]