I got a Lenovo X1 Carbon that is pretty thin and have a adapter for Ethernet, good enough for me and doesn't seem to have any performance issues. The form factor of the X1 makes me really love it.

But when it comes to smartphones, I agree. They are getting thinner and larger, possibly to make it easier to drop and break or something, because I sure don't get it. It's hard to find a good, reliable smartphone that is around 4 inches today so I can hold it without worry with one hand.