A friend of mine was talking to me and was saying how he always wanted to create after market parts for cars to make them look cooler or run better. He mentioned one of his favorite was http://www.chipfoose.com Chip Foose.
I made a post about this so you can join in on the discussion at the Gopher Small Business Forum here.
This is a business that can totally be started from your home. I think if I were going to get started in this, I would get an older car to fix up and I would make a website of the process.
I would experiment and create fiberglass molds to bolt onto the car to make it look really sweet. Things like hood scoops, fender flares, fins, whatever.
Then I would sell these after market parts.
Maybe I would even create after market fiberglass body panels. Over time I would add more vehicles to this and create an online catalog.
I would also host a hotrod night at a local parking lot. Maybe have it once a month.
Why not form a custom car club as well and create a forum for members to get together and talk about this topic.
With the ability to sell products on your website and have a paypal button to accept credit cards, it becomes so easy for you to reach out to people and sell your products, right from your own home with little money invested into it.