I will also agree with the Savannah. It is the only TRUELY large and truely domesticated cat. That is bigger then a bengal, or maine coon, etc etc. Bigger as in, they are longer and larger over all, but they are very sleek, refering to the page listed before, a perfectly skinny and fit Savannah can be between 18-29 pounds and I have been told that some are even bigger then that!
They are a cross between a serval (which is a wild cat) and normally bred with bengals, so they look like extra large bengal cats and fetch for anywhere from $1,000 - $3,500+. Depending on what generation you get.
They live in the house with you, they get all the same shots, they eat the same foods as little tabby kitten here. And they are said to be completely domesticated. But with any breed, you should fully research them before getting one.
Cats can already be tricky enough to manage, let alone a LARGE one.
I will own Savannah one day and it will be great. From the moment I saw them I told Kirt that I HAVE to have one. Their personalitys seem great, and it's one step closer for me working with the BIG cat species some day.
Though I will probably only be ever able to afford an F-3. :/
Their coats come in many different colour variations. And the patterns come in spotted or marbled. I would probably get one of the clouded marbles.
This is a GREAT example of what a savannah can look like.