I have actually had the effect hit me, but not knock me out. So let me be clear: You DO NOT trip. You DO NOT feel relaxed or at ease. You feel nothing. You are awake, with full motor control, and most of your cognitive abilities. You will have zero recollection of what you are doing, but will be able to do normal things. That's the problem, and the danger. You might drive your car, tell your boss what you really think, or, in my case, try to cook yourself some chili and nearly burn your house down.
It's why I stopped taking the stuff (which I was prescribed!). Again, there's no pleasure from it, no "escape" from the terrible reality of "being in the closet" as John says, none of that. You either take it and pass out, or take it and think you passed out, but hear about what you did later from others.
In fact, when I got it prescribed, it was specifically because it was the least habit forming or addictive option, according to my doctor. This was before they had Lunesta, which I believe has now surpassed it in that regard. But it's supposed to be non-habit-forming by design and aside from the fact you'll end up depending on it to fall asleep (but duh, you were an insomniac anyway) but you can't abuse it to get high.