Artist Jason Shelowitz (a.k.a. Jayshells) made a name for himself last April when his super rad Subway Etiquette posters popped up around town. The guerrilla marketing campaign didn't make the MTA too happy, as they quickly removed the 600+ posters around the city (our personal favorite? this one against nail clipping). The posters eventually resufaced on Jayshells' Etsy page, at $75 a pop.