Let me take a shot here.
You can combine AA and US miles for either AA or US award tickets. For example, you get 2 F Hawaii tickets on AA for 100K miles (may be using all of US if you want to keep AA).

For NW miles, unless you want to transfer miles from Marriott Rewards to make it 20K miles, you could redeem 10K miles for 2 Hawaiian inter-island tickets.

On CO, you could do same same as NW for award ticket or transfer them to Hilton Honors program.

Ditto for TW.

On DL, you can move 5K mile worth of points from Marriott for 2 domestic/Canada award ticket on DL or UA or you could move all DL miles to Hilton.

I don't think you could use UA miles. Seems like they are enough for magazine subscriptions.

Holiday Inn, you could transfer 10K pts for 2.5K miles of its airline partners.

I left a few but I'll leave them for others.

Why don't you use free services such as http://www.myciti.com/ or http://www.verticalone.com/index.html or other programs to keep track of your FF accounts? They can be such time saver...


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