<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by PremEx:
I even have many of the old Frequent Flyer "Flight Cards" from several airlines that you used to have to fill out with your name, FF account number, date, flight numbers, from/to airport codes...that you had to attach to every single flight segment coupon you used.</font>
I still use a variant of those... for Xiamen Airlines' MF Egret Mileage Plus (shades of United) and China Southern's Sky Pearl FF Clubs. They each mail a batch of about 20 FF-number barcoded stickers at a time, which you have to stick onto the ticket at check-in.