In the past few years, we have covered plenty of flat plasma discs here. The 16-inch Blue Square Luminglas is also worth a look. It is a touch and sound reactive flat plasma lamp with adjustable pattern and sensitivity. These were originally used in a game at Hershey Park Amusement Park.
These square Luminglas lamps were made in various colors, such as green, blue, and red. More info is available here.