Disclaimer: Don't own Doctor Who (or the lyrics in this story)
Snough were easy to catch. All you had to do was tune into their thought patterns by use of a metal headgear with antennae.
In other words, a tinfoil hat.
The Doctor had his when he bumped into a man walking the other way.
"Sorry," he began, but the man was staring at his hat.
"Um…" he began, trying to think up an excuse for the headgear, "it's a… bibbity-bobbity… hat."
"A frock coat… and a bibbity-bobbity hat?"
"Yes."
The man shook his head and turned away. The Doctor walked away as well, not sure why that sounded so familiar…