Same. I have many ideas for interesting products. These ideas are not of value in themselves and I'll happily hand most of them off for the asking (I would in fact back in kickstarter if anyone seems able to execute.)
Now, an idea + something else can be of value, but then it is beyond a mere idea. An idea which has been validated by market research to show its marketable and at least enough technical research to give a rough idea of development costs and production costs can be valuable, but then you have added a lot to it.
Even just an idea + a detailed plan for researching and then developping the idea can be valuable, but again that has at least added something.
I won't quite go so far as to say that a bare idea is worthless (absolutes often make me hesitate), but without something more it is worth very little.
