http://icanhas.cheezburger.com – Grandparent of silly cat photo sites, it now includes videos, gifs and lots of animals that are not cats. Also ads.
http://meowcheese.com – Much like icanhascheezburger only with not quite as many photos – silly cat photos with LOLs. Also like the cheezburger site, it has branched out and shows other animals as well.
Several episodes of Henri the Existential Cat, who speaks French and is ever so tired of life, can be found online. See, e.g., Henri the Existential Cat is back with a holiday message
http://www.simonscat.com – We see Simon and his cat in funny minimalist cartoon animations. The site also has silly cat photos, contests, etc.
http://kittenwar.com – The home page presents two photos of kittens, click on your favorite, see how many others agree with you, then consider the next pair. Kittens can’t lose.
http://www.squidoo.com/sillycats – Videos of silly cats, including an excellent Maru compilation.
http://stuffonmycat.com – Just like it says, but the photos are more amateurish than many on the web.
http://evercats.com – all cats and kittens — no dogs, sloths or frogs. New photos every day.
Sherry Maddill runs a fabulous custom clothing for cats and, yes, dogs. (We at PPK are not at all adverse to dogs, as you know if you have read Pride and Prejudice and Kitties). Sherry’s custom “jackets” make cats’ coast-to-coast flight safe while taking them out of their carriers at the airport! Visit: www.cattykittydesigns.com and www.facebook.com/cattykittydesigns