Archiving the World's Bathroom Graffiti
I was surprised to find that this subject didn't have it's own group, let alone a piddling discussion. But, progress takes time.
I'm interested in 3 (three) aspects of Grout Graffiti -
Penmanship (or penwomanship)
Knowledge and/or experience of grout, tile work, various grout products available commercially and institutionally (especially secret advanced grout technology of the military), plumbing