I just love cutting up the cardboard packaging from tea, cakes etc., and always keep a pile handy for lists, after which they go in the recycle-carrier bag...
We always get loads of stuff from Scotts of Stow, and Coopers of Stortford, (the latter won't get anything from me any more - they sold me a load of duff socks, and after two messages, ignored the issue), but we try and use any old envelopes when we can!
And birthday cards to each other, etc., get saved and reused every year, with strange names written on countless sticky labels, and lots of arrows and crossings out! It's always nice to see the old cards from the cats and the dog too, the paw prints and licks are masterpieces!