Like a poem, code makes an approximation of an ideal in the way that metaphor attempts to grasp something larger than itself with varying degrees of fidelity and success. In fact, #! expands the kinds of successes that code-based poetry can achieve.
“Rhymes with” poetry.
If memes existed in the mid-20th Century, William Carlos Williams would surely have propagated a few. Alas, WCW passed away before the age of the internet, but he left at least one poem to help future generations go viral.