The $2,500 light bulb...

Offhand, I'd say this is a solution for which there was no problem. Before I'd pay $2,500 for a light, I'd go back to candles and kerosene lanterns and spend the savings on good whiskey. 

As an old retired electrician, I have to agree with him  on one point: heat has always been the enemy of light-bulbs, especially incandescents, which, for some reason, designers have always tried to contain within fixtures having very little or no ventilation whatever. The hotter such a light has to operate, the shorter its lifespan, and we've known this ever since the invention of light bulb number one. And as the filament slowly vaporizes from the intense heat, it plates the inside of the bulb with a microscopic film of metal and combustion products, slowly blocking the emission of full brightness, and that's why old bulbs look darker and don't deliver as much light. And we've known that for a hundred years or so too.

Compact fluorescents and LEDs are improvements on the old tungsten-filament bulbs that got hotter than hell and burnt out relatively rapidly. Mercury-vapor bulbs also last longer, but they don't operate well in sub-zero tempertures, because they require a certain minimum ignition temperature that isn't always attainable if the ambient temperature is far below zero. Street lights in the far north sometimes will not re-light if extinguished in severely cold weather.

Mercury-vapor half-wave rectifiers have been used for many years as a means of converting alternating current into direct current for use by trolley and subway systems in major cities around the world. The originals of these rectifiers were made of glass, with 'arms' onto which electrodes were connected, and a pool of mercury in the base which was vaporized with the aid of a striker contact operated by a solenoid. The arms, coupled with the bluish flickering light emitted during operation, made these look like some kind of science-fiction monster gone wrong, but they delivered plenty of power for the trolley system for many years. They were only replaced with newer devices because the last two old gentlemen in England, where these special glass bulbs were made had reached retirement age, and there was no one to take their places. Or so the story goes. And that was the end of an era, for sure. You had to see one of those glass-tube mercury-vapor recifiers in operation to really appreciate what a chore it would be to create that glass container. They were about three feet high and about as wide, with their three 'arms' on the sides, and sat on a special base. And they looked really weird with a dancing arc moving around on the surface of the pool of mercury in the base. Like they belonged in a Frankenstein movie.... But they really worked!