Riddle #962

Dipping, glinting, gliding by, Rainbow-fretted, wrought of breath. I live only while I fly – Earth’s rough kiss my sudden death.

When you have me, you feel like sharing me. But, if you do share me, you don't have me. What am i?

My antlers tower above my head. Where I live it’s cold all year. I can pull a sled or pack a load. You call me a ?

I am the beginning of the end, and the end of time and space. I am essential to creation, and I surround every place.

Large as a mountain, small as a pea, Endlessly swimming in a waterless sea.

I drift forever with the current down these long canals they've made. Tame, yet wild, I run elusive, multitasking to your aid. Before I came, the world was darker. Colder, sometimes, rougher, true. But though I might make living easy, I'm good at killing people too.

I am slim and tall, many find me desirable and appealing, they touch me and I give a false good feeling, once I shine in splendor, but only once and then no more, for many I am "to die for".

Die without me, Never thank me. Walk right through me, Never feel me. Always watching, Never speaking. Always lurking, Never seen.

They fight against me day and night, They try in vain with all their might. But when I win the final strain, I close their eyes and end the pain.

Turn me on my side and I am everything. Cut me in half and I am nothing. What am I?

What always runs, but never walks, often murmurs, never talks, has a bed, but never sleeps, has a mouth, but never eats?