A business customer happened to comment the troffer lights in their realtor office were flickering, giving them headaches, and making their skin look green.
I said we could do something about it, probably recessed halogen. Then I looked above the drop ceiling and saw a maze of plumbing and HVAC crammed into the 14" space. The troffers weren't going to come out without major destruction of the ceiling. Then I talked to a guy at our supplier who know lighting inside and out and he suggested replacing all of the magnetic ballasts with electornic ballasts.
It was a great idea. We generated a lot of work out of that job, and the client got a huge refund back from the state's energy dept. (CA in this case) The light color was much better, the flickering and buzz were gone, and everybody was happy.
One minor nuisance was rewiring the ballasts. The color-coding of the wires is right out the window. I finally took the tombstones apart and made a schematic to work from. Also, my neck feels like a tree trunk from reaching up for so many hours. Those magnetic ballasts are heavy after awhile.
End of the story is that this whole thing started a word-of-mouth thing going that's generated more work.

Whenever I'm in an office now I always float the question- "Boy those fluorescent lights are kinda buzzy huh?"