Calle found the previously-mentioned lightbulb joke for me. You may now all feel entirely free to wish he hadn't. :)
How many B7 characters does it take to change a lightbulb?
The answer seems to be at least eight...
BLAKE: "Don't you see, the lightbulb must be given the freedom to change itself. That's why we're fighting!"
AVON: "It's not my field."
VILA: "I would change it, you see, only I've pulled a muscle. You really ought to give me something for that, Cally, the pain is terrible! Plus, I'd have to stand on a chair, and I'm really not good with heights."
ZEN: "This unit is not permitted to interfere with lightbulb-changing activities."
GAN: "I'm trying to change it, but my limiter keeps kicking in. Probably some Federation technician's idea of a joke."
ORAC: "That task is far too trivial to be worth engaging my circuits. Besides which, if you hadn't noticed, I do not have any hands!"
CALLY: "There is an old Auron proverb: 'A man who refuses to change a lightbulb is not in the dark, merely unilluminated.'"
JENNA: "All right, I'll do it, if you'll all just SHUT UP!"