What was something interesting you learned last week?

Some of the things I learned this week:

watchdog for python - cross-platform file modification watcher

There are two great sources of information that support the big bang theory - cosmic background radiation (that I already knew) and the relative densities of hydrogen, helium and lithium as observed with spectroscopy from the sky.

Ghosts cannot exist because they would violate the second law of thermodynamics. By extension, souls are a myth too.