*According to the Internet Meme entry in Wikipedia, The term Internet meme is used to describe a concept that spreads swiftly via the Internet.
According to Know Your Meme, many of the most popular lolcats memes started via 4chan.org. Every Saturday, posting under Anonymous, a 4chan.org user would start Lolcat threads on Saturdays. This soon became know as Caturday.
LOLCat Bible - Oh hai. In teh beginnin Ceiling Cat maded teh skiez An da Urfs, but he did not eated dem.
Trotskyite on hasn't been updated in while, but what is there is very good. As one poster defined the blog, it is "the juxtaposition of a completely outdated and oversimplified conception of the Soviets/Russia that entered the West via the Cold War against a modern fluffy humor meme."
Totally independent of LolCats, Keyboard Cat, was uploaded to YouTube, and the rest is INTeRNeT HiSToRy. Keyboard Cat is so Famous that he even has a Wikipedia Entry and others Played Him Off with their own Keyboard Cat parodies.
Another popular Internet Cat,Standing Cat, also began on YouTube. There were other standing cats and people mimicking standing cat and he quickly became a Meme.
Before there was Super Net Star Piano Cat, there was Nora the Cat the original Piano Playing cat who was a meme in her own right.