I always got that feeling when I was trying out systems of composition. Usually stuff where there was some mechanism by which music ended up being made, which wasn't informed by my tastes in any direct way. I think all those were really interesting experiences and I revisit them often, because there is something there that I can't consciously create. Just like a set of counterpoint rules are agnostic to your music tastes, there are a lot of techniques that color music in ways that you would otherwise not even think of doing without them.
So, I'll give you an example:
And you know how the score looks for this?
That's process music, right there. The instructions create sound, yeah, but there are so many things left to the interpreters, to the room, etc. It's experimental in that each musical result is different every time (it's not exact at all.)
Is it a piece with a concept? I don't think so. Steve Reich thought it was kind of funny if it's done right, supposedly! The actual sound you get from this is quite strange, but I think the greater lesson is not that microphones and speakers make weird noises, but that you can extrapolate this into just about any genre of music. It all depends on what kind of system you want to use, how exact you are about it, and what degree of "randomness" are you willing to accept.