That kind of stuff can go far in the right hands.
@OP: How protective are you over the ideas? Posting them to HN will probably find someone to build them. The risk being you might be bypassed in that process. Is there a way to give your knowledge / plan enough value that a would be "builder" wants to work with you?
"Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats." -Howard Aiken (i think!)
I guess your concern is valid. But, most people are that way, the ones that really are motivated enough to complete a project or build a startup already have their hands full with ideas of their own.
If you have researched your product and have a definite vision of it, then that's what you bring to the table. A stolen idea would look, well.... stolen!
The problem is putting enough info out there to get interest without exposing all of your work.
On the other hand if their left on the shelf doing nothing then, well, that is possibly even worse.