Haiku, as far as I can tell, is some sort of Japanese poetry.
I know that there are many rules to take into consideration when writing formal haiku, but the advantage of bad haiku is that you don't really have to follow any of them. On this site, most people do 17 syllable haiku structured in a 5 / 7 / 5 form.
So, basically, if (so ba si cally if)
you can speak in syllables (u can speak in syl la bles)
you can write haiku. (u can write hai ku)
The Bad Haiku site has been on the internet and accepting poetry since 1996. It was down from 18/06/03 to 5/07/05. It is lightly moderated.
Occasionally, the site gets mentioned in publications. Here's one that's still up:
Chicao Sun Times