I really like the idea of The Internet Wishlist - a platform where people can submit ideas for applications and websites they would find useful. Demand-driven design through crowdsourcing, really.
From the creator Amrit Richmond: "I hope the project inspires entrepreneurs, developers and designers to innovate and build the products and features that people want...I see so many startups try and solve problems that don't need solving... I wanted to uncover and show what kinds of day-to-day problems people have that they want technology to solve for them." (H/T Good)
It would be great to have a similar platform for Data.gov (and similar initiatives), bringing together not just the developers and crowd-sourced ideas, but also people that were familiar with the data/ content that is actually/ potentially available. Of course this could get messy when someone tries introduce IP to blossoming project...
- sezflom