Projects like the wonderful "Minimig" by Dennis started as a thread if I recall. Several other long time Amiga related sites have many neat projects that start from a single thread or idea, often from one person. The community builds on them by adding yet even more great ideas or suggestions. Sometimes it goes nowhere, other times a new product is born.
I think we need all of our great minds assembled one place to brainstorm new ideas, no matter how unrealistic or impractical they may seem at the time of discussion.