The Lykovs– For 40 years, this Russian family was cut off from all human contact, unaware of World War II. In 1978, Soviet geologists prospecting in Siberia discovered them.
DPGraph– check out the extremely psychdelic website for this actually quite dull maths software
1920s time capsule house– almost nothing has changed in this Belgian house for nearly a century
The Sonic Youth tuning tutorial– tuning guides for almost all their songs
China only has one timezone, and that’s a problem– how people in Xinjiang in the far west of China deal with having an official timezone that makes no geographic or practical sense (this is also the same region that is currently being heavily repressed by the Chinese government)