Not really a cash back site, but I kind of like these survey sites. And some of them give you cash for your time, this one included. I've made £34.30 on this one to-date, which isn't bad going, it's one of the best for payouts on filling in short surveys, so if you don't mind telling them the brands you like, car you drive, well worth a shot.  Who knows it might even push the big companies into being more ethical, if that's the feedback they get.

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