At my high school there was a courtyard with a concrete patio where you could look out over a grassy area about ten feet below. One day at lunch I sat on the edge of the patio and tried to imagine what it would be like to fall from that height--how soft would the ground be, how likely would it be that I'd twist something or break something, how far would... and then I just jumped. And I was fine.
I like a straighter "appeal of the void" but I don't think that's as accurate.
As for me, I don't know how to describe it exactly...mostly an intense curiosity or reflection about just how interesting it would be for myself and everybody else if I jumped. After all, you'd be able to see practically unique sights that nobody in the world has seen before...
This reminds me of some famous lines from Pushkin's "little tragedy" Пир во время чумы / Feast During the Plague (1830):
Есть упоение в бою, И бездны мрачной на краю, И в разъяренном океане, Средь грозных волн и бурной тьмы, И в аравийском урагане, И в дуновении Чумы.
There's rapture in a battle, bliss Upon the brink of the abyss, And in the raging ocean's fury, Midst angry waves and darkness vague, And in the desert whirlwind's hurry, And in the breeze that brings the Plague. (Translated by M. E. Yankelevich)
Wait a minute--all this talk of tingly urges, voids, and aiming makes me wonder whether we're talking about the same thing. When I look over a cliff, I get an if-only-I-could-fly, followed by an irrational maybe-I-can-fly, tempered by a what-would-happen-if-my-camera-fell, which causes my knees to go involuntarily weak.
I discussed this with a French friend of mine a few weeks ago while overlooking Rustaveli Avenue in Tbilisi from a third floor balcony (which are ubiquitous the country over). She had just returned from Stepantsminda, a very beautiful mountain town to the north, to which I have not yet been. Her comment: "It might not be a good idea for you to go; there's a lot of vide there."