13 
Engineers at GE’s NELA Park facility recently discovered five intact lightbulbs inside a 100-year-old time capsule. And much to the delight of the dudes over in marketing, three of the century-old bulbs still work.
The tungsten filament bulbs needed a little cleaning after being removed from their temporary tomb, but once connected to a socket and slowly powered up to 60-volts, the majority of them slowly came to life. They’re obviously not as bright as modern bulbs which run off 120-volts and use more efficient filaments, but claiming a 100 year shelf life would be impressive even today. [GE via BoingBoing]
I don’t see why these bulbs shouldn’t have worked. I would assume that Fluorescent, Halogen or Neon lights would have suffered some leakage of gas over a similar period which might have stopped them working but so long as they were kept away from oxidisation of any ferrous parts or heavy vibration to break the filaments these bulbs should have been fine indefinitely.