They have big keys, the keys can be labeled ... But the idea of using a cash register for a custom keyboard is interesting, and certainly a lot of work is already done for you if you don ...

If you find yourself wishing for even more functionality, you might want to build something like this custom macro keyboard ... software that runs on them. The key to most builds is the 32U4 ...

If you're looking for more control over how your keys feel and sound ... it's easily the most customizable way to build your own custom keyboard without diving into the expensive parts world ...