Found somewhere in the Net, that cats can drink sea (salted) water.
This fact seems to me as being urban legend, not true (because the purpose of water in body apparently implies it should be clear).
What is true and how to explain?
Since cats are well adapted to dry environments, the question has some plausibility to it.
The book "Mineral Tolerance of Animals" suggests that cats may be able to tolerate slightly more salt in their diet than dogs (1.37 g salt/kg body weight for cats, vs. 0.64 for dogs). However, these represent concentrations that were shown to be safe, not the maximum they could potentially tolerate. The reference in the book is Yu et al., 1997, and though the actual reference is not available in the Google Books version I believe it must be The minimum sodium requirement of growing kittens defined on the basis of plasma aldosterone concentration, so the goal was to identify minimum rather than maximum levels.
The ocean is about 3.5% salt. The 1.37 value for cats came from kittens eating a diet that was about 2.5% salt, but another note in the book says that cats can safely eat a diet that is 3.8% salt, though they don't like it. I can't find the original reference ("Berger, 1979") for this claim, but I am pretty sure that this was with ad libitum water so they could flush out extra salt. If so, cats would not be able to tolerate sea water unless they had another source of water as well.
It's often said that wild cats can get most of their water needs from their prey's blood. It's also sometimes said (incorrectly) that the salt concentration of blood is like that of seawater; this is not true (blood is more like 1% or less NaCl) but it may be the source of the statement.