Anil Dash has a great post about them, in which he identifies a number of lolcat subclasses and discusses kitty pidgin, the mangled English used in many lolcat pictures. Kitty pidgin is surprisingly regular, which I suppose means, as Anil Dash puts it,
that cats can has regular
A number of sites collect lolcat pictures, among them I Can Has Cheezburger and Meme Cats. If you browse through those sites, you’ll quickly get a feel for how lolcats work. If you’re inspired to make your own, remember: use Impact or Arial Black, and put a black outline around white letters.
While this is nice and all, I quickly realized that there are no long-form lolcat works. The closest is Spatch’s wonderful Cat Town, and it’s only a relative to lolcats. That set my fevered brain to spinning: what would a lolcat story look like? What if lolcats had a TV channel? What kind of shows would be on it?
The answer is clear: they would show Star Trek."
The entire Tribble episode in LOL cat at granades.com