Trolly's lovely piece on flying reminded me of one of my heroine's more prosaic approach to astral travel...

Sarah found herself looking at herself sprawled on the bed. She shook her head sadly. What a mess! Slowly it dawned on Sarah that she was actually looking at herself and not just thinking it.
"Great!" she thought, "I'm now quite mad. This is all I need!"
And it slowly dawned on Sarah that perhaps this was not madness after all and she might just have actually left her body...
...Excitement took over. Now she'd experienced something she would really learn how to do this astonishing thing. A wicked thought bubbled up: "Murder by Proxy!” She had a vague memory of a horror story she'd read in her teens. It was something on the lines of a man 'training' his out-of-body self to manipulate objects and committing murder with a well-aimed ashtray. Satisfying thought, but not really her style. She wasn't feeling murderous just sad and confused...
...Sarah had a wonderful time. "All the advantages of the Invisible Man stories without the hassle of the clothing dilemma" she thought as she planned the big operation: spying on them together!

A spanking story with astral travel....now there's a thought!