Any body collect Civil War collectables out there, and if so what do you collect

My daughter used to collect Civil War collectables. It was a rather odd passion for a teenage girl I think. But she still has some of the things she collected. Mostly small things as she didn't have the money for any large items. She started after the husband of one of my friends showed us his collection. His was very extensive. He had even been to some of the hidden areas in under-ground Atlanta (the real underground Atlanta, not the shopping district) and told us about some of the things that are still hidden there, like an antique train engine. Very few people actually know how to get into these areas. I would like to go - I think it would be very interesting.