I'd like to take a moment and address this thread, although I know it's pretty much dead. The questions of whether a hobby is worth it, if it doesn't make money or at least gain recognition and a blurb in a history book is an important questions, especially with conlangs and conworlds, which hardly ever receive any attention, outside of even the most learned of "nerds".
For me, the idea of a conlanguage is tied up with a conpeople, conculture, and a conworld. I'm majoring in Philosophy and minoring in Linguistics and Spanish, and so needless to say I'm interested in the philosophy of language. To create a language without speakers is like painting without a canvas, or performing music without a musical instrument. Even more so, I really think that a "legitimate" conlang needs a conpeople, conculture, conmythology, and ultimately, a conworld.
When I first got bitten by the conlang bug, when I was 13, after reading LotR for the first time (yep, a bit cliche I'd imagine) my first efforts at a language was hardly even an English cipher, and now fast-forward 10 years. My interest in conlanging, and ultimately in conworlding has truly spurred my academic career and mental development. I was not satisfied with my results, and that drove me to learn and to research, and before I knew it I had gone from an average pudgy non-athletic bookish teen and became immersed in philosophy, linguistics, history, music, and literature, among many other things. I'm hardly a polymath, more of a "jack of all trades, master of none" type. But while I have never finished a conworld, more often than not scrapping the entire project in disgust and starting anew, I have learned from each endeavor, and I have learned even more in general. In a way, conworlding (broadly speaking) is more useful than college, as far as actual learning goes.
Sure, a lot of people want to end up with "something", at the end. A book, a body of literature that everybody loves (and with faithfully recreated movies of it), a role-playing game, whatever. Those things may happen, at which point, everyone else is now free to botch your words, revise your histories, and steal scores of your original ideas and use them for their own projects (D & D, Tolkien is rolling in his grave). At that point your work is the property of the community, at least intellectually or culturally. It will then exist beyond your own life, and so will you, in a sense. Or, you may never finish a project in your lifetime. But it doesn't matter. It made you happy, or in the very least it entertained and engrossed you.
Is that such a bad thing if it doesn't make millions of dollars? Or if no one ever learns your languages or reads your conencyclopedias? Maybe, maybe not. It's all up to you.
All I know is that sometimes when I am writing, or researching, or creating, I feel a 'something', a 'something' that is just beyond my grasp of explanation. It's not inspiration--it almost seems to be the object or source of inspiration. Like I can almost reach out and grasp it, and have in my possession what my mind has been searching for. I can read a story, or of an aspect of a culture, or a word in a foreign language, and a feeling almost like deja vu comes over me. Like what I'm searching for is SO CLOSE, that I can almost be reading about it right now, in these very real books, and yet so far away. In a way, it feels as though I am reading about my own 'true' culture, the one I ought to belong to, whether it exists or not, that I have almost been subconsciously creating for myself, and then in a strange way, I am confronted by it, and yet it is still not real.
I am using a great many words to describe something that is such a profoundly subjectively personal of an experience as to almost make words meaningless. All I can say is that all of my efforts at conworlding and at researching in this present world are all worth it when I experience this sensation of truly connecting to what I'm searching for. It adds a profound sense of mystery and wonder to the mundane world that I live in now, where our search for truth and knowledge has driven all mystery into hiding, whether for good or ill, to the point that genuine mystery or ultimate inexplicability are disguised in trite platitudes or playing dead coyly under the boot of reductionism.
If my conlangs and conworlds never are 'completed', are never read, observed or appreciated by another, or never make a dime, I will count it all as gain. My work has been instrumental in where I am now, and in helping me to grow and understand where I am now, in this modern world. In the truest sense or the word, my conlanging and conworlding attempts have been Art.
And I now know how the True Artist feels, regardless of where his or her paintings are hung.