I go by ZOD, ZODone... aside from it being one of Supermans greatest enemies, I like the block that the word produces and you can really play with those shapes too. After copious googling, I could not find any one else with that name, although it wouldn't shock me if there was someone with the name thats had it longer than I have.
When you're looking for a name it's always best to choose a name that is quick to write, flows well, and doesn't give away anything that might link you to your graffiti....
theres bound to be at least 1 if not more people writing the same name as you are. Just make sure you're not writing a kings name or someone real famous' name. also make sure they're not in your city.
Say a word, any word, listen to the sounds/syllables. If the word is unused or not common it shows that you have creativity and you didn't just 'rip' a name from a word. Also, you can take a word (Possibly something meaningful to you) and put into Google Translate, translate it into Hungarian and see what shows up, listen to how its pronounced too.