The key fobs are unique, but too unique because the system is not open and we don't have access. But there is a really cool relay for power supply's at Ada Fruit
There has been some talk about access control and people have brought up both sides of the coin on that. Currently we have the sticker system, and it's intentions are good and it works for most of the equipment.
In Nick's case he has been very generous and got burned on it, this is something that nobody likes to see. I think the move that Nick made for people that want to use his equipment to buy the consumable parts will do a great amount to mitigate poor use.
The problem is that the tool will no be open to less people, but I don't think this will necessarily be a bad thing.
Another step in the process could be to have a plasma cutter kit available for purchase at the space. There are some easy ways to do this too, but it will involve some sort of management, and may in this case be more hassle than needed, I can't make that call, but if there are interested parties I have some ideas that I think would work.