My United miles were about to expire so I spent 1,000 miles on a $25 Restaurant.com voucher. The expiration date for the miles has been pushed back 18 months so I'm happy. If anybody wants this voucher, PM me and I'll give it to you. When you apply the voucher, you will see a $25 credit to purchase gift cards as usual.

Should combine with % off codes.
http://www.flyertalk.com/forums/showthread.php?t=347721