Cats in Sinks is a web site that posts pictures of, um, cats in sinks. There are more of these than you might think.
Neither of our cats would be found in a sink if their food bowl was in there. But apparently the sink is a popular hangout for your typical Felis silvestris catus, who just loves to curl up for a nap in the porcelain.
Miss Woodhouse and Miss Darcy especially enjoy a warm radiator.