I wanted a ring that was simple yet unique. I have really small fingers for a guy (size 7) and unfortunately every time I found a nice ring, it was too large. So I decided to make a pair of matching rings (one for me, the other for my girlfriend) out of a solid block of aluminum and the most basic of tools that almost anybody has at their disposal.
Overal Cost: $0.00
Step 1: Cutting down your block
I looked many places for an aluminum block that was small enough to not cost a fortune yet big enough to make a ring out of. After exhausting my options, I decided to ask the machine shop down the street from my house. Three minutes later I left the shop with the perfect block of aluminum -- for free. So as long as you ask the right people, these rings will be completely free (but they are a fair amount of hard work).
So the first thing to do when you get your block is to cut it down into a more manageable size. I used rectangular stock because that was all I had access to; however, round stock would obviously save a lot of time.