I ran around town about six months ago looking for green, unroasted coffee beans. I was a little surprised by how few coffee baristas knew that coffee beans start out green and end up brown only after they've been roasted in large drums. (A couple of these same baristas also shared the story of the origins of Kopi Luwak with me, as a possible explanation for how coffee ends up brown.)

I was looking for green coffee beans because I was interested in trying to roast some myself. There are a number of ways you can do this; they all involve merely keeping the beans in motion over heat for ten or twenty minutes and then letting them cool for about twelve hours. I ended up doing mine in a Whirley Pop on the stove, and the results, for a first attempt, were surprisingly drinkable.

For those who don't want to mess with a hacked solution at home, you can get good, small drum roasters for coffee online for about $500, which have a reputation for being easy to use and producing good results. For most people, this is too large of an investment just for experimenting.

I'm really surprised that nobody's opened a coffee shop that lets people buy a bag of green coffee beans and then roast them with one of these machines. The quality of the resulting roast is irrelevant. Most people probably wouldn't get it right the first time, but it does give people the opportunity to play around with a craft that would otherwise be too expensive to get started doing.

I think there's lots of business ideas that could be started around this model. It's not just "do it yourself"...it's offering people an intriguing way to spend an afternoon, and to make something they can call their own.