The only context in which "m8" is acceptable
would be if you're talking about Cheetham, Greater Manchester.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Fri 15 Aug 2008, 18:21, archived)

Cheetham innit m8

( Jenk Neptune is a pedant and now I can't fit my sig in, Fri 15 Aug 2008, 18:21, archived)

I was trying to be street, down with the kids etc
;)
( its_hatorah_bitch is b3ta the devil you know on, Fri 15 Aug 2008, 18:22, archived)

I saw Kids, apparently you need AIDS to be down with them.
Not the good kind, either.
( Jenk Neptune is a pedant and now I can't fit my sig in, Fri 15 Aug 2008, 18:23, archived)