I don't, and the effort required to find one when I need to invoke a warranty is one of the major stresspoints of my life. (See ironing thread...) I was wondering today if I would ever have the discipline to take a photo of any receipts for major purchases, and store them in a dropbox folder. Or even just use a box that's easy to reach to stuff them into. Every so often I clear out my whole purse into somewhere or other but in such a disorganised way that I wouldn't know what box has receipts from when. And they all go in there so I've got receipts from takeaway meals along with expensive tech stuff that's likely to go wrong. Sometimes I think I shouldn't have been allowed to be a grownup, I lack some of the crucial basic skills.