Sometimes, I swear people actually watch my shows. Hard to believe, I know, but consider The Big Bang, now playing in endless repeats on Discovery Kids:

A few months after we did a cute trick involving dropping a cork so it lands on its end, a game appeared called ‘Corx.’ Which is… er… based on the same idea.

Then there’s the pneumatic marshmallow cannon we made in a later series. It was breech-loading and used a cunning arrangement of cardboard tubes and bin bags to make a neat step-down from a large-diameter piston chamber to a small-diameter barrel. It was astonishingly accurate, though an unforeseen problem involving marshmallows melting under studio lights rather limited its effectiveness on camera.

Great toy – one of the best things we invented on that show. Clever, elegantly simple, extremely effective. And now available commercially. Huh.

The tragedy is that the lead times of television are so radically different to those of other industries that we never managed to make any tie-ups work. Even the books we did featured material from the previous series, and arrived after the one we were making. Shame.

But for the record – no, I’m not sore about this. There’s no particular reason to believe that the designers of the marshmallow gun were inspired by The Big Bang. In fact, I’m delighted if kids are running around blatting each other with pneumatically-projected confectionary. It’s a lovely mechanism.