A few hints on making ‘Infinity Mirrors’.
One ProMini, some code, 47 neopixels, acrylic frame and some woodworking skills can result in a nice gift idea (or 6).
https://www.tapplastics.com/product/plastics/cut_to_size_plastic/acrylic_sheets_mirror_clear/521
https://www.tapplastics.com/product/plastics/cut_to_size_plastic/two_way_mirrored_acrylic/558