If you're interested in a good redemption ratio, I found an interesting Diners Club three-step, transferring into the SAS program, then using SAS points for hotels.
They have a pretty attractive deal with Radisson Blu (formerly Radisson SAS) throughout Europe and in the middle east (I think) where weekend stays with breakfast are 10k points per night.
1 DC point = 1 SAS point...gives you a European weekend night for US$100.
I would do it in smallish transfers (more because of some question in the SAS forum about the future of the hotel program), but there's a slick interface in the SAS webpages to do the reservation online.
JL