Language and the internet

Since it’s been annoying me a lot for a while now, I’ve decided to compile a list of annoying spelling and grammar errors, etc. commonly practiced on the net. Then possibly construct a resource to promote the art of typing properly.

So what I want from you is the things that annoy you most about the way people talk on web sites and message boards, IMs etc.
for example: 1337 speak, txt abbreviations, misuse of there/their/they’re, stuff like that.

Gentlemen, start your engines.