Factoraly

Hats have been around for a while. Egyptians and Romans wore them, and so do food delivery riders today. This one's all about this ubiquitous headgear.

Sheep are part of our heritage. We have worn woollen clothing forever, we have walked on woollen carpets from Axminster. We have work sheepskin in fighter planes and in used car lots. There's more to sheep than black or white. Click on the pics, as always, for shaggy stories.

The telegraph revolutionised communication for peace, war and finance, not to mention birthdays and weddings. Simon's feeling poorly this time, so our friend Greg Dwyer stands in for him and telegraphs an excellent performance (as usual).

Fans have been keeping us cool for centuries, from huge ones that cool a whole room to small ones that flutter and send messages. We hope this episode makes you one of our biggest fans. If only...

We all make mistakes. Sometimes they make things better, sometimes, they make things worse, and sometimes they end up creating whole new industries and products!

Trivia is, by its nature, a rabbit hole. This time, we've decided to take a look at the animals that make the holes. Rabbits.

NASA is so well known that it's synonymous with space exploration. This time, the rabbit holes you'll enter by clicking the pics are more like wormholes!