Scratch paper, grocery lists, and if you use binders for coupons, you can cut leftover paper to size to use as pocket dividers.

I have taken a piece of paper that's just printed one coupon and fed the blank end back into the printer to print another q on the blank end. (I mean without cutting the first q out first.) Other words, blank end -- don't think side matters -- goes into tray toward the printer feed. I don't want to mess anybody up though and risk causing them to print a q on the very back of another q, so maybe test with something simple and non-coupony, like text, at first.