So I did some research about Letterboxes and stamps, and I came across this how-to on how to make a stamp from a rubber eraser. Last saturday I bought some cheap, good-sized erasers to experiment with, and we still had a cutting set (which klik stole from her highschool...), so I was all set.
As designs, I chose the happy cat () and sad cat () that Tempy Royale with Cheese uses to show which episodes he liked and which he didn't like. I scaled the pictures to fit on the eraser, printed them out and transferred the toner onto the eraser with acetone (hmmm, how refreshing!). Then I set out to do some cutting.
The happy cat is a bit... manic -- probably because of the Joker-like grin. Still, not bad for a first try, I think.