Smoke & mirrors! I really don’t have an exact formula but try experimenting with Sky & Fog and in particular Haze. Try changing colour and intensity. I used reflective surfaces in this one too. I find the Alt + left mouse butt very handy (when trying to get an exact colour for example).
LOL I was afraid it was something like that. I tried fooling around with a round parallel light in the lab, and got something looked more like a colored glass tube than a laser beam. Oh well, it wasn't a total loss. I'll try using primitives instead of actual lighting and see what I get. Thanks for the tips