I'm afraid this is me being a bit self-indulgent. After I saw an art-work by the artist Mark Wallinger which consisted of 1000 bricks all with his first name chalked on them, I thought I'd extend the idea - by marking a number of brick walls in my locality in much the same way. My first name is Mark too.
The photo you see is a montage of some of my efforts.
Of course my work is temporary (the marks were gone after a week of rain) and Mark Wallinger's pieces are a lot more valuable... but I enjoyed the experiment of the comparison.