Friend: (Answers phone) Hello?
Me: (Crappy song playing really loudly! I let it go for a little bit and then hang up.)
Plus, it works even if they let it go to voicemail.
Then I text them: You've just been "audio Rick rolled"
Other potential songs:
Sisqo - Thong Song
Fergie - My Humps
Hanson - Mmmbop
Baha Men - Who Let the Dogs Out?