One thing especially rewarding for me has been rebuilding carbide lamps and getting something posted online for others to access so these great little "machines" can live on. I learned about them many years ago when my awesome uncle introduced me to caving. I have fond memories of exploring a certain southern Indiana cave where Teddy Roosevelt left "carbide graffiti" on a cave wall. We used battery powered lamps but it left an indelible impression on me and a quiet fascination with old carbide miner's lamps.
Now I've been able to bring that to a less quiet level and rebuild a couple fairly derelict examples and see them come to life!
If you are curious or even better, have an old lamp sitting around and want to resurrect it check out the Instructable for a fairly in depth how to on rebuilding and repairing them. It's everything short of re-sealing a breached carbide chamber or re-braising broken joints and if you can do that there's nothing you can't fix on these cool old lamps.
http://www.instructables.com/id/Rebuild-A-Carbide-Lamp/
