Gallium's melting point is slightly above room temperature - if you hold it in your hand it will melt. Mischevious students used to make gallium spoons, and provide them alongside tea. The prank's target would use the spoon to stir their drink, and the drink would 'eat' the spoon.
Stomatopods (also called Mantis Shrimp) are generally ridiculous. The larger ones can strike with the force of a small caliber bullet (and have broken aquariums made of double layered saftey glass!). Their strikes are so fast that they create cavitation bubbles, which collapse in bright flashes of heat and light that then send shockwaves that can stun fish. They have trinocular eyes that can see ridiculous numbers of colors, including circularly polarized light. Some species are bioluminencent. Some species, if they get washed onto the beach, are capable of flipping themselves into wheels and cartwheeling back down to the water. Oh, and some species mate for life!
Hagfish have no spines, and they take advantage of this fact to tie themselves into knots. By moving the knot down their body, they can scrape off the slime that they generate and leave it in the mouth of whatever hapless predator thought that eating a hagfish might actually be a good idea.
There exists a real creature called a hydra. They're small fresh-water creatures in the same Order as jellyfish. They're so called because if you cut a hydra's top part (I hesitate to say head) in half, it can regrow each half into a new head, like the myth. Also, they can be turned inside out without causing obvious harm.
The original title of Robinson Crusoe was The Life and Strange Surprizing Adventures of Robinson Crusoe, Of York, Mariner: Who lived Eight and Twenty Years, all alone in an un-inhabited Island on the Coast of America, near the Mouth of the Great River of Oroonoque; Having been cast on Shore by Shipwreck, wherein all the Men perished but himself. With An Account how he was at last as strangely deliver'd by Pyrates.
Hong Kong is an island and a country, but not technically, as many think, a city. The capital of Hong Kong is Victoria, or at least it was until China took over in 1997.
It requires some planning. You start knitting a stockinette background (pure knit stiches). Then you knit a few rows of purl stitch and one row of knit. You then unravel the purl stitches in section, leaving some loose yarn, and pick up the loops at the top of the stockinette section. You then do a few more rows of pure purl stitches, partially on top of the previous purl section and partly on the original stockinette section. Then you re-purl with the loose yarn that resulted from the unravelling.
Speaking of tin, in vacuum solder will form “tin whiskers” that grow out as thin metal filaments. This was discovered when early spacecraft kept short-circuiting after launch.
I know that “I have a song to sing, oh” from Yeomen of the Guard is one of the only (possibly THE only) song for which Sullivan required Gilbert’s aid in creating the melody.
You can’t revive the thread without contributing something of your own! Those are the rules that I’ve just up.
I know that A Martian Odessesy was written at least in part to satisfy a challenge by a SF editor (whose name escapes me) to create aliens who have intelligence that is equal to, but different than, human intelligence.