[King Prout]

"Tie a Yellow Ribbon Around the Old Oak Tree"

ok, you just upped the stakes by making me remember the entire gestalt of the pre-Reagan late 1970's

[Miss Marple]

Here's another one:

Knock three times on the ceiling if you love me,
Twice on the pipe, if the answer is no.

Ugh. Now I have THAT one running through my head!!