What is it, that's always coming but never arrives??

What has 6 faces and 21 eyes??

I have my mark and am asked to be answered, what am I ??

I travel all over the world, but always stay in my corner, what am I ??

What goes up but never goes down??

What word has hundreds of letters in it??

If you say my name and I am no more, what am I ???

I never speak unless spoken to. Many have heard me, but none have seen me. What am I ???

What can fill an entire room without taking up any space??