Answer:
I'm light as a feather, yet the strongest man can't hold me for more than 5 minutes.
A nut cracker up in a tree.
Once they sailed the sea, now they surf the web
Golden treasure I contain, Guarded by hundreds and thousands. Stored in a labyrinth where no man walks, Yet men come often to seize my gold. By smoke I am overcome and robbed, then left to build my treasure anew
Each of these ends in a kettle full of precious metal and the double variety is quite awesome
You use it between your head and your toes, the more it works the thinner it grows.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?