Being properly unconscious. No dreams, no waking up, no nothing. Usually induced by an ample supply of alcohol, and a mixture of melatonin and kwells travel sickness tablets. Perfection.
i am not sure i have ever experienced happiness to the point of oblivion.
but the closest i can think of is when i am floating in the water, on my back, sun on my face, eyes closed. i love that it is quiet and muffled. i love that i can let my body go, let it be weightless and held. i love seeing the sky, and only the sky. all the blue, all around.