How to make a Windows Time Capsule

ExtremeTech has a item about a home made Windows Time Capsule as a competitor of the sleek designed but overprized Apple Time Capsule. It's funny to see you can mimick the functionality of a $500 device with a solution for less then $200 or about the same amount in Euro's because of VAT in Europe. Building your own NAS is much more fun of course but the proposed solution will do. And you know you should at least backup your documents and photo's, right?