Can I trap a gas in a beer bottle with an ordinary bottle capcap?? I would like to trap neon gas in a beer bottle with a bottle capper. My goal is to build a plasma ball (tesla ball) in a beer bottle so I can have corona in my corona :P. I plan on building the tesla coil into the bottom of the cap, so that I can pop it on and be good to go. I am planning on using a circuit similar to this one built into a light bulb (which already has the gas trapped in it): http://www.rmcybernetics.com/projects/DIY_Devices/homemade_plasma_globe.htm At this point I really just need to know if there is a practical way of filling the bottle and if a bottle cap will provide a sufficient seal. Thanks.