Marc's Napkin
I got the idea for this from Mellan's Veronica's Napkin, which was
made sometime in the middle of the 2nd millenium. Mellan made an
etching of Jesus by making a single spiral and varying the thickness
of the line.
I thought this was really cool (at least for its time) because the at
the low level, it's just a spiral, but Jesus's face emerges at the
higher level.
In making these, I tried to balance between seeing nothing (besides
the spiral) when viewed up close to seeing my face clearly when viewed
from far away. That is, I wanted to balance between recognizability
at the top level and non-recognizability at a lower level.