The contrast with the high-tech phone and its materials (glass, aluminium, ..) and the natural look of solid wood, makes this an impressive case.
Cases like these can be bought at webshops, some examples are :
But of course it is much more fun and rewarding to make such a case yourself.
Just as much as the iPhone is a precision device, manufacturing this case will require precision.
Apart from that, with basic tools and very little materials, you can build a really impressive protection for your phone.