LumiSource is behind some of the coolest plasma lamps we have covered here. The LumiSource Mini Moai Plasma Lamp is also worth a look. It is an Easter Island inspired lamp that looks blue when turned off and becomes green when you turn it on. It also reacts to your touch. You can use it as a physics toy to excite all kinds of gaseous elements.
These lamps are pretty hard to find, but they show up on eBay once in a while.