What I find quite delightful is the way someone will foolishly post an innocent and reasonable question which will then generate a thread and mutate quite quickly into something completely different.

For example:

Poster A: My daughter just broke her leg and we're waiting for the ambulance. Should we use a wood splint?

Poster B: How did she break her leg?

Poster C: Woodn't she get a splinter? Hah hah.

Poster D: I broke my leg when I was skiing in '78.