While they were never much money, I guess I'd say the dumbest thing (ie not as functional as I would have thought) would have been a few wood humidors I purchased earlier on in my career. They look beautiful but as y'all know they don't keep a seal well. As I've migrated to wineadors (or a couple rogue Tupperware containers to house some overflow) I've given away all of the wood ones I had purchased previously.