Episode 6x07: Numb3rs describes the Internet Relay Chat protocol, a "pretty primitive chat program". It's how hackers talk when they don't want to be overheard. Oh, and they use leetspeek! "LUCKILY, I speak leet."
ENHANCE! ENHANCE! CROP! ROTATE! ZOOM IN ON THAT REFLECTION!
PS: now captioned in english and 1337 (f0r r34l h4x0rz!)