This book: http://www.amazon.com/Refuse-Choose-Revolutionary-Program-Ev... helped me identify myself more.
I got this book for my wife: http://www.amazon.com/Could-Anything-Only-Knew-What/dp/04405... and she said it helped her refocus things.
The takeaway from all of this is that TMA page helped me identify and 'diagnose' (in a loose sense) that condition. The Sher books above helped with some practical advice on how to live and deal, and sometimes thrive, with the condition. Her term for someone with TMA would be 'scanner' , and she's written about scanners for years.
I've been juggling things for a while, and currently I'm a publisher (groovymag and jsmag), a consultant (really just consulting sometimes), a developer (hands on coding), a trainer, speaker (2-3 conferences per year), have written a book, and am working on some other projects for later this year which may help open some doors in to new avenues.
Had I stayed at my job I would have been more compensated financially but far less fulfilled. That said, I still wrestle with feelings of unfulfilledness, and some of that comes down to not being able to execute on all my ideas. What I'd like to do is get to the point where I'm comfortable hiring people to do a lot of the grunt work fulfilling my ideas (I don't particularly care to do the work, I just think it needs to get done).
This doesn't mean I'll never take a traditional full time job again, but I'm a lot more demanding and critical when I talk to potential employers. That still comes up now and then, and I'm a lot of aware of myself and open when talking about employment. Nothing has yet fit the bill, but I'm not shutting the doors to that possibility. I just don't think it'll be likely. It'll need to be a kickass company and/or working in an extremely engaging problem space with some freedom for me to float around some. Very few traditional jobs fit that bill.
I have what I think are some pretty awesome web/software ideas, but I only ever spend a few days in a row working on them because coding requires that sort of singular focus that I can't maintain for much longer than that.
And then now there's potentially (probably) a girl in the mix, so who knows what's going to happen...
-Robert A. Heinlein
Have you heard of the Kolbe spectrum/ test?
It helped me evaluate my strengths/weakness a lot. It's unfortunately not free, which I think prevents it from attaining the credibility it deserves.
I really like the way it thinks: http://www.kolbe.com/ (No affiliation.)
It has a TMA-esque category It really helped me self-diagnose... and diagnose others, heh heh.
Basically it got me off of binary skill judgement of both myself and others. (Less "that person is awesome!" or "that person sucks!" and more about how job design is usually the issue, rather than people.)
It's taken me a long time to stop being as judgmental about people as I've been in the past, and to start recognizing and appreciating the particular skills and qualities others have. It's not easy to recognize in others when you measure everyone (and yourself) against perfection.
I'm not sure many of the psychological tests out there are free, and likely having one 'officially' administered wouldn't be free anyway. I had my IQ tested as an adult a couple years ago by a friend's wife who needed to run these tests as part of her phd work. Apparently it's quite easy to find kids to test, but few adults were willing to put themselves through it. I hadn't realized the 'instruments' cost so much money, but there's a big industry in psychologically measuring and evaluating people. It shouldn't have been a surprise, but it was.
Just like the OP I find it difficult to sustain my interests for a long time. I have been trying for my own startup for the past one and a half years. I start on ideas with very high initial enthusiasm, but in a few weeks I have given up on the idea and jumped to the next exciting one. Looking back on the last one year or so I feel disappointed with myself for wasting possible opportunities. But many thanks to the OP and all other good HN'ers for throwing more light on this issue. I feel I understand myself better now, and i'm going to approach my interests with a new sense of purpose. Thanks again.
"Being given a list of specs and then coding to the specs is just not my kind of thing" I bet creating the architecture for how the problem will be solved in the first place is more your kind of thing. I used to think every programmer wanted to be an architect, then realized a few years ago that wasn't the case.
Hang in there, and keep working at it!
Medical aspects aside, it sounds like you've not been able to find a niche yet. I'm not trying to trivialize this, but you obviously do have some passion (as others note) but you can't channel it in to something productive for very long. It also sounds like you're trying to do this all on your own.
There are people who remain stuck in one routine for years or decades. You have the ability - probably a compulsion - to get in to new situations routinely. Believe it or not, this would be seen as an asset in many organizations. A 'presales engineer' position (if you're technical) might be a great position to get in to, as you're constantly getting in to new situations and people, most of whom you won't need to deal with a few weeks or months after the sale is made.
Without sounding trite, suicide isn't the answer. You've likely got quite a lot to offer. You're on HN after all ;) I hate to just say 'go get counseling and medication' - I think there's probably other things you can do outside of that, or in addition to that course.
I realize I don't know you much, except for what you've posted here, but I really don't think things are as hopeless for you as they may feel right now. I don't think I've had things as bad as you're describing, but I am known for an extreme inability to focus/concentrate on anything for very long. I don't tout it, but have worked on coping strategies over the years. Eventually I found a book by Barbra Sher (http://www.barbarasher.com) - well, she's got a few. Wishcraft might be a decent one to start with. It's free, and while a bit airy fairy at times, might help you to see things in a different light. I was first turned on to Sher when I was reading up on the problem of TMI (Too Many Interests).
http://knacks.esmartdesign.com/#The_Too_Many_Aptitude_Proble... was the first article I'd found, which seemed to describe me to a T. I've since self-diagnosed myself with that 'condition' and went looking for info which would help me learn more about that. There's no 'magic bullet cure', but that bit of self-knowledge has helped me avoid situations which I knew would make me miserable, and have slowly forged a better, more fulfilling life (though even now, I keep changing my goal posts).
The biggest thing I learned from that little journey is that there's nothing 'wrong' (in an absolute sense) with that condition - it's just different.
If you'd care to discuss any of this further, please ping me at any time at [email protected] or 919-827-4724.