I am NOT trying to contend Silence, he's still the best riddler and magician with words. I am just wanting to have my fun, as he thought I would. ;D I just want to take track of them here, since I think I have some nice ones to share.
Made the solved solutions invisible, so everyone who wants can try and find them out themselves again. :] Just mark the stuff between the | with your mouse and you can read the solution again!

#1
This riddle is not by me.
SOLVED BY ASBJORN
German:
"Das Kalte mache ich warm,
das Warme mache ich kalt.
Es hat mich Reich und Arm,
was lang mich hat, wird alt."

My Translation:
"I make the cold warm,
And I make the warmth cold.
Rich and poor have me,
If you've got me for long, you're getting old."

HINT: You're using me right now.

|It's "Breath" as Asbjorn correctly guessed!|

~~~~~

#2 I thought of this one myself yesterday. :]
SOLVED BY TERABETHA
"You are a a tall man,
But I'm just as high as you.
You are a small man,
Yet without any troubles
I am at the same eye level as you.
I am not that far away
But you will never reach me."

|Alright, Tera, it's the horizon!|

~~~~~

#3 This, again, is not by me... Rather easy I'd say... ^^
SOLVED BY SHIMMYSHIMMY / SILENCE
"What does the human like more than life,
what does he fear more than death,
what owns the poor one, what is the rich one missing,
what do wish these, which are satisfied?"

|Silence was right, it's "Nothing".|

~~~~~

#4 By myself.
SOLVED BY SHIMMYSHIMMY / SILENCE
"You gave birth to me,
But as soon as you're gone, I'll die.
I am you
But I am another one, too.
Can you name the two?"

|Their names are water and ice, as Silence revealed.|

~~~~~

#5 By myself. Rather easy. ;D
SOLVED BY SHIMMYSHIMMY / SILENCE
"Every animal is awarded to one of the elements;
Fire, Water, Earth or Air.
Some in two, but tending to one.
There's only one species
That masters all elements
At the same time."

|These are the humans, right, Silence.|

~~~~~

#6 By myself. Try specifying here, please, to make it easier for me to say "True". ;]
UNSOLVED YET
"If there is only one of him,
He's getting kicked
And is in the way.
If there are many of him,
He's getting kicked
But he is greatly appreciated."

HINT: Many of him are not natural actually; someone put them together...