I once experienced the carpet morphing into a fractalized Aztec mandala, which I then fell into and spiraled downwards through into a vast lime colored underground sea in a cavern full of purple bats.
This happened while I was trying to have sex (amazingly, we succeeded, it helped that my wife was sober).
I have seen then on the brushed aluminum of my laptop at the time on regular (large dose) LSD… and I certainly see them (and strings connecting the present to the “future” on n,n-DMT.