I tracked my spending similarly a few years ago - you don't realize how much money you waste spending a couple of dollars here and there. Good thinking tacking the receipts inside, because then you always have them to return items back to the store which equals saving more money! hahaha
I'm a math major studying in northern Ontario - it's pretty friggen cold. I am seriously considering knitting one of these for my favourite professor (a topologist) when I graduate. I know he will love it.