All you IT'ers and lawyers have plenty of lightbulb jokes already wriiten for you, but I've crafted the first ever Preservationist lightbulb joke by myself. To wit:

Q: How many Historic Preservationists does it take to change a lightbulb?
A: 6. 3 to form the non-profit group FODDER (Friends Of De-lighted and Damaged Electrical Resources) to protest any changing of the bulb at all; 1 to prepare a study report that proves that this is the very lightbulb that inspired the first "lightbulb" joke in 1774 ("How many blacksmiths does it take to light a candle?" The punchline has been lost to history); 1 to determine that simply repairing the lightbulb might be the best option; and 1 very well-paid consultant to write the report for the developer funding the lightbulb project that determines that changing the lightbulb will have no adverse effects on historic resources after all.

Perhaps it's only funny to those in the field, but I was inspired (you know, a light bulb went off in my head).