Hi Y'all

I have about 18,000 miles on Northwest which will expire at the end of the year. I would like to transfer these miles into one of the following accounts:
United
Continental
American
Sheraton
Hilton

Currently I cant think of way to do this. Does anyone know of a way. Hilton allows other airlines to transfer miles into Hilton Honors points, but not Northwest.

If I cant transfer the points, I would like to redeem them for something. Any suggestions. By the way, I never fly Northwest anymore. I try to stick with the carriers that I have the most miles with.