Ok, so I am trying to find a way to make this matrix shown here, in LaTeX:

I tried to search for this type, but I frankly do not know what one would call this, so I had to draw a picture shown here to illustrate what I mean. So basically, I want a matrix, but I need to make lines as rows as shown here, with the respective $$x_i^T$$ shown as well.
Would appreciate any help, thanks.
\bigg|. There is no such easy solution for the horizontal lines, which motivated the question. – kan Apr 10 '13 at 20:51