This gets a 10 out of 10 for being an awesome idea! The Wedding Ring Workshop, as you can guess by the title, is a make your own wedding ring class for couples. One testimonial reads.

Jim & I cannot thank you enough for the wonderful experience we had making our wedding rings! It truly was a romantic and creative adventure; something we will always recall with a smile...

The FAQ page will cover most of your questions. Including a few great ideas such as how to incorporate a piece of family heirloom jewelry.

...it can be melted and added or it can be attached, so long as the metal is the same purity as you have chosen for your rings.

Their sister site in the UK offers this video.