I needed a scraper for the Craftbot and the others on here where a bit too big so I decided to just make my own. This is about the size of a business card. I changed the design just a bit to make it better. I made the hole a bit larger and moved it towards the center so that you can place the thumb on it. The size also makes it easy to use on any side and angle with just your fingers.

Update:
March 31, 2015
I have found that over time the edges on these gets broken and well, used. I used a sharp cutter to trim the edge and I now have a brand new sharp edge to use again. So don't throw them away, just trim it and you're good to go for a while longer with the same scrapers.