It's the sincerest form of flattery, people say. And so it doesn't surprise me that the lolcat meme has taken on a couple new species.
(What's a meme? Yeah, that term has been kicked around a lot in the latest year or 2. A meme is a piece of cultural information, like a song, that catches on and filters out to the population almost like genes either make it or don't -- without people really trying, but the good ones survive.)
I thought icanhascheezburger was pretty funny with their whole subset regarding the tragic tale of the walrus and his bucket. But lolwalrus has not got his own site (that I know of so far).
Lolrats, however, do.