I just received a mailing from United regarding this very subject. Use your orphan miles for magazines. I have only 3837 miles, awaiting a 1000 mile survey bonus, and will make a short flight to reach 5 or 6,000 miles and will turn those into 10,000 Hilton Honors points. Also looking forward to UA/US merger and to see if my 40,000+ US miles will turn into UA miles.
[This message has been edited by newself (edited 11-05-2000).]