This involves a touch of philosophy, but it's actually quite practical: not too long ago, my wife and I were sharing a meal, and I recalled Carl Sagan's brilliant presentation about the 4th dimension, using Flatland as example. He deployed an apple (I can hear his voice in my head now!) to describe how utterly alien a concept 3 dimensions would be to the people of this 2D world, and how the 2Dians would just see the "edge" of something so much more.
In much the same way, I've come upon the realization that I often leave sideways ideas in the open — nested amongst other ideas at times, standing by themselves at others, but hardly ever deliberately hidden. They however, remain available for use by anyone able to interpret them usefully.
During the meal I mentioned earlier, I used a napkin to illustrate how I fold an idea sideways — turning the napkin so that you only see its edge. My wife then took the napkin and elaborated on the concept, unplying it and referencing deeper layers.
It's more than an inside joke, and not meant to be an elusive puzzle: to the right people who understand certain points of reference, a construct can easily be assembled and contact with the idea-pollinator made. Further actions can then happen. But these are precious ideas worthy of not just anybody; it takes an uncommonly common understanding to, as they say in geek, grok what you're about.
Maybe you can relate, if you've put an idea out there but didn't make it blindingly obvious, and you were waiting for other likeminded souls to come along and call you out on it. Perhaps secretly, you wished to find friends this way who would really "get" your creativity.
If that's how you feel, I've known that feeling all too well. 
Sometimes I put a lot of stuff out there that is completely open - no hidden parts. It's just that many people are blind sighted or just don't realize what it is that they are looking at until you explain it to them. Then they can discover the other aspects of you with this newfound "key". It's that social connection that is missing I guess where people are more interested in each other than the content of a stranger.
I am on a lot of these social networking sites as well as "social content" sites (flickr for example). People see a picture, smile, and go about there business. They don't realize there is more to you (a stranger) than a picture, and that the other content may lead to something fantastic such as a learning experience, artistic awe, a formation of ideas over time, or simply a suggestion of ideas.
Or it could be that people just don't have the time or ability to be inspired.
@Dedric: Yes, so true. It's such a joy for me to have things discovered by people who "get it" — perhaps they've had the same shared experiences earlier in life, perhaps they've recently seen media (pop-cultural references) which relate to what I've put out there, or otherwise.
I'm often interested in "the story behind the smile". Not just the end effects or even the initial cause, but the processes in-between, too.