Fan Nickname - Often referred as ZQ or La Quinto. His Carpet of Virility is known as The Batsignal, and his most recognizable trait is known as the Sybrows. Characters he has played are known as Quintoplets.
Fan Community Nickname - Zachary has a very dedicated and loving community known as Sylar's Army.
Hipster - Generally looks like he fell out of a Urban Outfitters store, frequently spotted at places associated with hipster culture, and tends to tweet in all lowercase, complete nonsense, and the Hipstamatic photo app.
Actor Shipping / Launcher of a Thousand Ships - Has an uncanny ability to create disturbingly natural chemistry with anyone he so much as stands next to, whether it's in character or not. Examples have included Matt Bomer, Jonathan Groff (although that's canon), Chris Pine, Zoe Saldana, Kristen Bell, everyone who's worked with him on Heroes and Star Trek, Zachary Levi, and the list goes on. You name it, there'll be a fandom that ships it.