i believe this is the current standard in this area
http://www.albinoblacksheep.com/text/leet.php
although this only goes from normal to 1337, although it allows you to specify the "1337ness" of the text entered, which is pretty badass.
--b£00Ðn1nj4
edit: just checked yours out, pretty damn cool man! only problem i had with translating my name was that it saw '1' as 'i'. by definition, since "leet" is called 1337, shouldn't '1' be 'l'? anyway, cool prog, i'm gonna hang onto it. must've been difficult considering 13375p34k is so damn unstandardized.