I've had a rough design for something like this in my notes for a while now, under the heading "what do to when you can't buy incandescent bulbs anymore?" It's

I've had a rough design for something like this in my notes for a while now, under the heading "what do to when you can't buy incandescent bulbs anymore?" It's a serious concern for me as my collection of 30 or so Lava Lamps (from the 70s through modern ones) are far less interesting when they're cold.