I remembered this thread while working on a couple cars at the rock house last night
I was useing a cheap but nice plastic drop light ( $5 at wallmart) and a $4 CFL in it. It is half closed all the way around. Course this light is not used all the time like a normal house light would be, but the bulb is probably over a year old. I hang this light from a tree in the yard for a yard light often, it has been in hot and cold weather, as a work light under the vehicles it gets bounced around and rough treatment, and of course it is always being turned on and off.
I am actaully suprised it still works. With a normal 75-100 watt bulb I would have blown a dozen or more, those little bumps blow bulbs fast. Also I was tired of getting burnt when I bump into the drop light using the metal ones and the plastic ones melt from a normal bulbs heat. So far replacing the bulb has saved back the cost of a CFL bulb just with how many other bulbs I would have went through already, savings in power usage is great also since I run it off an inverter and battery.
I wonder how long this one will actaully last. No way to judge the hours, but it stands up to abuse pretty well