As the price of diamond continues dropping, I wonder if people will find more interesting applications of the material and it'll eventually become as mundane as things like steel and aluminium. Besides its hardness, it also has very high thermal conductivity. Diamond is still too expensive to be a bulk material, but I look forward to when things like this become cheap and commonplace:
https://en.wikipedia.org/wiki/File:Single-crystal_CVD_diamon...