Webb Mirror (2022)
neil.fraser.name
neil.fraser.name
https://www.youtube.com/watch?v=gOpbXBppUEU
The guy makes his own lenses, and loves to explain what he does
There have been some attempts (including a couple by Mythbusters) to replicate the legendary heat ray of Archimedes, but it looks somewhat implausible with the tech of the time.
https://en.wikipedia.org/wiki/Archimedes%27_heat_ray
However Richard Hammond did have an toy experiment at Keck with a mirror with a diameter of about a metre and did have some success: https://www.youtube.com/watch?v=ix_tsqKzkrQ&t=3384