I actually haven't heard a lot of good ideas, even on this forum. Ideas may be a dime a dozen, but good ones, even if not followed through on, are still valuable, since someone else may take them up. I've certainly come across a lot of things I wouldn't even have thought of on my own, and am glad others were nice enough to toss them out. Also, Bitcoin, Namecoin, DIANNA, etc are all just a process of people throwing out ideas.