So, to say that something is in the ether means that it is something being communicated from place to place; it has no precise location, just as a radio broadcast can be heard from many different places.

What does floating in the ether mean?

Ether is a word that refers to the invisible force of life that exists in the air and space around all of us (it's used in mystical contexts, and was believed to exist by some old philosophers). Over here, he's using it poetically, to mean "empty space". He's suspended (hanging or floating) in the ether.

What does out of the ether mean?

So, if a person is "laughing out of the ether," I imagine he is laughing like he's quite drugged-up and not totally conscious or clear-headed.