It's a throwaway line that people use to describe something, usually an experience, which is so good, that it exceeds the standard of awesomeness established by sex. (Debatable as that may be to some people.)
I recently spent a furious hour or so working on my next novel. During that time I forgot myself completely. I was so engrossed and energized, that time evaporated. Nothing else existed except the drama I was creating in my mind and transferring to the page. When I finished I was intensely satisifed with my work. It was not a one off experience. Writing always slakes my thirst. That's why I do it.
I got to thinking about other times when I lose myself in the moment. When the world fades away, and there are neither past recollections nor future considerations nagging my thoughts.
Here then, in no particular order, and by no means exhaustively stated, are five "lose myself in the moment" activities.
2. An extreme fairground ride, like Superman Escapes.
What things or activities make you forget yourself and all your worries?