1. Happy Cat

He wasn't the first "lolcat" but this British shorthair with a perpetual smile and appetite for "cheezburgers" was the first to launch a media empire. With seven popular humour sites, including Fail Blog and a reality show on Bravo, the Cheezburger Network has no one else to thank but the late Happy Cat for raising $37 million in venture capital.

2. Grumpy Cat

No other cat made a bigger stink this year than Grumpy Cat. After her frown infected our inboxes and Facebook feeds, it started appearing outside of the screen too – in Time, on Good Morning America and at SXSW. For a Friskies ad, the cat food company supposedly treated her to a first-class flight, a five-figure fee and filet mignon. That ought to put a smile on her face.

3. Lil' Bub

She might have dwarfism, six digits on each paw and a deformed mandible, but we didn't see Robert De Niro pet anyone else at Tribeca Film Festival. And what was the slack-jawed, surprise-eyed Internet celebrity doing on the New York red carpet? Attending the premiere of her feature film documentary, Lil' Bub & Friendz.

4. Street Cat Bob

London busker James Bowen might have overdosed on heroin if it wasn't for Bob wandering into his apartment building. Not only did the chubby ginger's love give Bowen a reason to clean up his ways, he inspired the busker to write his bestselling memoir, A Street Cat Named Bob – and 350,000 copies later, it's being eyeballed by Hollywood.

5. Maru

What's so great about a cardboard box-loving cat? Ask the people behind his YouTube videos' 200 million hits. Ask the Amazon users who've left glowing reviews of his photo book and DVD. Ask the Japanese companies paying for Maru to sell their products. Seriously. Ask them. Because we haven't got a clue.

6. Hank the Cat

This Maine Coon found his way on the ticket of the last U.S. Senate election, placed as both a joke and protest against a dysfunctional political culture in Washington. He donned a tie, had a pro-spay and neuter platform and raised $60,000 for animal rescue shelters. Once the write-in votes were tallied by the Virginia elections board, Hank placed third with 7,300 supporters.

7. Oscar

Oscar was written about in the prestigious New England Journal of Medicine but you'd probably rather not know why, in case he shows up at your door. The hospice cat inexplicably cuddles up with patients mere hours before their last breaths. It has believers and skeptics debating the extra-sensory powers of pets.

8. Henri

With countless kitty flicks out there, winning the Palm D'Or of cat videos is not easy, but someone had to take top prize at the Internet Cat Video Festival. This French furball, who's black and white like his art-house films, won over jurors with lines of Camus despair, such as "I wake to the same tedium. Immortalized on a wall. Forgotten on the floor."

9. CC

Though she hasn't made the news in years, her birth got the kind of attention usually reserved for celebrity babies. CC, or "Copy Cat" – the world's first cloned pet – didn't lead to the commercial success predicted for pet cloning services, but she gave us yet another reason to hate the filthy rich.