There's a woman named Veronica Seider who had vision 20x better than average. She could identify people more than a mile (1.6km) away.
22
You can hear the blood flowing through your ears if you find a quiet place and cover them tightly.
17
Brass doorknobs automatically disinfect themselves in about 8 hours.
18
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9