ok, your mission should you choose to accept it is to identify the sound!

I am prepared to answer yes/no questions but I will try & avoid providing any clues… So the question is specifically how was the sound created? It was recorded in real time & hasnt been processed or manipulated at all:
I remember when i was a kid they used to have something like this on the radio. (And yes there is a prize, although i haven’t decided what it is yet)
via email
“I think it’s a closely recorded lead pencil point being drawn/pulled over
a piece of corrugated cardboard…”
nope
via ichat
“sticky tape being pulled off a roll?”
nope
Hmmm. Similar to last guess, but; masking tape or similar being applied to a cardboard box? The mic being nearer the box than the mic. But the really low frequencies at the start make me doubt this guess. Intriguing.
Oops – “the mic being nearer the box than the TAPE” is what I meant.
nope, no masking or sticky tape involved…
I’m only 7 years late;
Is it a comb being grated against the corner of a cardboard box?