English to HaXoR (leet-speak) Translator
HAXOR Translator
If you want the true history of haxor and leet-speak, this should explain the where it came from well enough.
Are you l33t? If not, you can use this translator to convert your text to H4X0R script kiddie language and look like a retard all over the Internet.
If you really want to go full retard, try out the English to English Translator... It's much cooler (seriously).