Basically a glorified still like the moonshiners used, but much prettier. And MUCH more expensive. It isn't the making it, it's the running it in today's autos that is the problem.
From http://auto.howstuffworks.com/make-your-own-ethanol3.htm <A solar ethanol still can usually be made with simple materials often found around the house. Building a boiler and a reflux column can cost anywhere from $30 in blueprints and about $50 in materials, to around $200+ for a fully-built reflux still on eBay. If you really want to make it easy on yourself, you can buy an EFuel100 MicroFueler for about ten thousand dollars.>