One of the more useful things in my bag after the IPMS show was a new pack of abrasive sticks. I'm terrible at changing these things when they are badly worn as you can see from the state of the old ones. In my defence, they still worked quite well when handled properly, but you couldn't sand up to the edges of the stick.
I'm like this with knife blades too. I know a sharp blade is a joy to use, but the parsimonious bit of me (I have both Polish and Scottish blood, neither nation is known for throwing money around) wants to make it last just a little bit longer.
Anyone else do this?