Dmist

English – Hello (formal), Hi (informal)
French – Salut (informal, silent "T"), Bonjour (formal)
German – Hallo (informal), Guten Tag (formal)
Bavarian – Grüß Gott (Gruess Gott)
Northern German – Moin Moin
Arabic-based languages – As-salaam-aleykum (Peace be on you) or Marhabah (Hello)
Surfer – 'tsup?
Spanish – Hola (pronounced without the H sound, ola)– Buenos Días (morning), Buenas Tardes (afternoon and early evening), Buenas Noches (late evening)
Slovak – Dobré ráno (good morning) Dobrý deň (formal - day), Dobrý večer (evening), Dobrú noc (night), Ahoj (informal)... or you can just say: na zdravia, na štastia, na lásky, na sexu (for health, luck, love, sex)
Italian – Ciao (informal), Salve, Buon giorno (Morning, formal), Buon pomeriggio (Afternoon, formal), Buona sera (Evening, formal)
Calculator - 07734 or 14
Norwegian – Hei (both formal and informal), god dag (good day)
Welsh – Helo
Hacker/1337 – |-|3||0 or |-|1
Tsonga (south Africa) – Minjhani (when greeting adult people)– Kunjhani (when greeting your peer group or below your age)
Japanese – Ohayou gozaimasu (O-HA-YOH GO-ZA-EE-MAS) (Morning); Konnichi wa (KOHN-NI-CHEE-WA) (Daytime or Afternoon); Konban wa (KOHN-BAHN-WA)(Evening); Moshi Moshi (MO-SHE MO-SHE) (When answering the phone)
CS-addict - b00m headshot!
Gangster - Holla (formal), yo (informal)