
By that standard,
Penny is CUCKOO for Cocoa Puffs.
The Big Bang Theory Season 4, Episode 9

Oh, yeah. The Mr. Spock CUCKOO clock.
The Big Bang Theory Season 10, Episode 10

I always thought
I was more like a CUCKOO bird.
The Big Bang Theory Season 1, Episode 15

was for CUCKOO pills.
The Big Bang Theory Season 7, Episode 7

I thought it ended at CUCKOO.
The Big Bang Theory Season 1, Episode 15