Answer:
A precious stone, as clear as diamond. Seek it out while the sun's near the horizon. Though you can walk on water with its power, try to keep it, and it'll vanish in an hour.
In we go, out we go. All around and in a row. Always, always steady flow. When we'll stop, you'll never known. In we go, out we go.
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.
They try to beat me, they try in vain. And when I win, I end the pain.
People are hired to get rid of me. I'm often hiding under your bed. In time I'll always return you see. Bite me and you're surely dead.
Why was the cook arrested?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?