As soon as in 1984, Hermann Czech publicly exposed his thoughts about the spatial effect of mirrors. The Italian bar he designed in Vienna in 2016 offers astounding amounts of space for a few m². Its sophisticated details may also be functional: the acoustic panels hide USB ports for mobile phones.
http://www.cincinbuffet.at/
https://www.facebook.com/Cin-Cin-Buffet-189817024738995/
https://en.wikipedia.org/wiki/Hermann_Czech
https://www.youtube.com/watch?v=4Lig8Uc8_uk
https://www.guiding-architects.net/en/destinations/vienna/