The Lord's Prayer in L337. One of those things that you stumble on and instantly realise it was inevitable that somebody somewhere had done at some point, and then you go "oh, there it is". Which isn't to say it isn't hysterically funny:

0ǔr $¥$@dM!n, \/\/|-|0 ©|-|!££$ !n |-|34\/3|\|
(Our sysadmin, who chills in Heaven)

(etc.)

I particularly like the ending:

"For thine is the network, and the rm -rf /, and all our base are belong to you, forever and ever."

Amen.