Which is your favourite Blender Wizardry?

Dear Community,

which is your most favourite or most impressive Blender wizardry? Blender is a universe full of unlimited possibilities, like:

  • someone uses a hair particle system to build a city
  • someone else uses a decimate modifier for an unexpected change of topology (I found this example a couple of weeks ago here on the forum and was really impressed)

So, what I mean is a maybe simple but unexpected use of a tool to achieve an astounding effect or result which would otherwise maybe take days to achieve otherwise.