nowadays quite a few brands have windows tablet. personally, I'm using a lenovo yoga book and a surface pro 2.
if you want something really portable and can do simple surfing, YouTube, word document or excel lenovo yoga book is a good fit. however please note, I used the word simple, as the unit lags the horsepower for doing too much stuff at same time.
my pro 2, though much older and heavier... still runs great. so much so that when my keyboard spoilt, I bought another keyboard off Amazon to continue using it.
but now I'm looking to get the surface book 2 15" version, for more power and simple gaming while still relatively portable.