It was 'cheers'
Your little sign off would be
(|-|33|25
/\/\4|2+1/\/
Of course other people have their own little styles and quirks.
so ( = C, |-| = h, 3 = E, |2 = R, 5 = s (though when talking of onez skillz one should always use a z, otherwise no one will phear you sufficiently)
/\/\ = M, 4 = A, + = t, 1 = i (but can also be used for L, see 133+), /\/ = N
But really, it's a free-style art form, so you can play around and find an alphabet that suits you.
Important phrases:
1 4/\/\ 133+ - I am leet
1 \/\/1LL H4X0R u - I will haxor you
PH34R /\/\7 /\/\4|) 5K1LLZ - Phear my mad skillz
U R T3H 5UX0R - You are the suxor. NB: 'The' must ALWAYS be spelt 'Teh'
Basic translation: I'm really fantastic. I will use my fantastic abilities to cause you untold problems with your computer. This will cause you to become rather wary of my incredible abilities. I do this because I believe that you are lacking in such skills and need to learn some respect for my prowess.