Here's a niche keyboard for just that task. It's called Trickey and it allows you to customize keys to do whatever it is you need them to do. It comes in a 6 key USB configuration but you can plug multiple boards together to create larger sets of keys. You can also print your own labels for the keys to go under the transparent key covers.
It's currently being prototyped - the developers are doing a Kickstarter campaign to raise funds - and expected to ship late this year. They're a bit expensive ($139 for the Kickstarter pre-order), but if it takes off, expect cheaper knock-offs.
As the Internet of Things takes off, expect to see many more specialized, niche tools like this.