prarul - Welcome to Flyertalk! As mentioned previously, getting miles out of an airline frequent flyer program is usually an impossible task.

Instead, why not try the complete opposite. Rather than getting miles out of the BA/Northwest/Delta programs or crediting extra miles through flying. Why not consider transferring enough points into these programs so that you can then book a free flight which will then take the total down to 0.

You mentioned that you have points in SPG. From the attached link, you will see that SPG normally transfers points to most airline programs at a 1:1 ratio. Indeed if you transfer 20,000 points they will give you an extra 5,000 mile bonus^

http://www.starwoodhotels.com/prefer...eem/index.html

Good luck with whatever you decide. IMHO the Alaska/US/Southwest Airways balances seem too little to mess about with, so you may want to gift them to a charity as suggested.