What is your experience with airline frequent flyer programs? Are they a good idea or not?

I have an air miles credit card. I buy almost everything with my credit card, and pay it off every month (therefore no interest). I end up getting a free flight somewhere every year. Works for me.

Good idea to encourage and reward loyalty; but too many restrictions, limitations, conditions, exceptions and exemptions. When you finally acquire enough points to do something worthwhile that you want, you can't!

I did the same thing as Strangerland. Tons and tons of air miles I can never use for the same reasons as wanderlust. Total waste of time.