The White House Open Government Initiative is a really big deal along these lines, much bigger than people know.
We're also seeing remarkable innovations across the country, like in Manor, Texas.
There's a guy leading remarkable stuff there, Dustin Haisler, who takes a good look at some of the software for such purposes:
These platforms (like Ideascale, Uservoice, etc.) are great a gathering ideas for a specific purpose. For instance, many online voting challenges have adopted these platforms to gather votes for a set period of time. After a user expends their vote or votes they are no longer motivated to return to the platform aside from seeing what ideas are on top.
This type of platform (like Spigit) collects and manages ideas on a board scale within multiple departments of an agency. Unlike the Specific-Task Motivated Platforms, users are free to submit ideas at any time within multiple departments. Since users are not motivated by specific-tasks, they must be motivated by a game-mechanics (ranking & rewarding of actions). In this type of platform, ideas are driven by the participants through an idea funnel.
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