my dad had google earth installed on his toshiba laptop and this was one of the coolest features ever
Google hid a fully working flight simulator inside Google Earth back in 2007 and never told anyone.
You unlocked it with a secret keystroke: Ctrl Alt A. No menu, no announcement. One user stumbled onto it, the combo spread, and it got popular enough that Google made it official the next year. Two planes, an F-16 and a Cirrus SR22, flying over real satellite imagery of the entire planet.
Then it stayed locked inside the downloadable desktop app for 18 years. The browser version was a stripped-down viewer that couldn't run it. Today that changed.
Here is the part that makes it impressive. A flight simulator is the single hardest thing you can ask a 3D map to do. Panning is easy, the software has all the time it wants to load the terrain ahead of you. Flying low and fast strips that away, forcing it to fetch, decompress, and render the world faster than you are crossing it. The hardest possible job for every part of the system at once.
So "just for fun" is carrying a lot of weight in that sentence. Getting this to run in a browser tab is the cleanest proof that the web version finally matches what used to need a desktop app.
The toy is the benchmark.