FTD is giving 20/$1 through the end of the month...Will run you $150. (Feel free to send some on my behalf to my girlfriend...Not the whole $150, of course, just a nice $80 arrangement).

Other Mileage Plus Mall partners are out there as well too...I recall doing a Giftsense purchase and the miles were in there in a week or two.

Are you signed up for dining for miles? (AKA iDine)...Most participating restaurants give 10/$1. Depending on the time of the month, I have those post in about 3-4 weeks.

Have any hotel points? You can transfer Hilton and Starwood points for UA miles. Same w/Amtrak. The quickest transfer I've ever had was Diners Club to UA (but didn't that go to 1-1)?

To further the above paragraph...If you have Continental One Pass miles, you can do CO-Amtrak-UA. All in, about 12 days to complete that one.

Several options...Letting us know better what you have available in other programs, your time frame, and your budget (for buying stuff to get miles) might allow us to address your needs better.

Finally, did you ASK United if you could go negative in your account? They will do that depending on your flight history, your status, etc.