If you think plugging a flourescent lamp into a light socket to replace the incandescent bulb is a thing of recent years, take a look at this:
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It's a 20W fluro light that plugs into a bayonet socket. I bought this unit in 1981 but had seen them since the late 1970's. The construction is the most interesting thing. It's basically a plastic tube with a bayonet plug mounted in the centre and the control gear inside. That's the interesting part...as you could imagine a heavy iron cored choke hanging from a bayonet light socket could be a bit heavy. So they use a resistor...
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You can see how it's constructed through the hole left by the bits of broken plastic (the UV is to thank for that). It's just like a radiator element except the tube is glass instead of quartz and the resistance is a higher value (about 500 ohms). It's the first commercially made flourescent lamp I've seen using a resistor. Needless to say, efficiency isn't that great, drawing .4A at 240V (about 100W). The other thing is that the tube used in it needs to be one with a starting strip, as there is no inductive kick back to fire the tube when the starter opens. I don't think the makers ever envisaged it, but it will work on DC mains.