You can use Ubuntus Brainstorm for your own projects it seems. But "we are working on making Brainstorm project-neutral" indicates that it would take some customizing right now.

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Now that I'm thinking of it. A big company like Nokia could easily develop a 'brainstorm' like site if they wanted to. Why would ideas collected on an independent site have any chance to be implemented if Nokia didn't see a need to set one up by themselves in the first place? I think you need cooperation of Nokia to have any effect.

And I did bring it up once here. For some the 'enhancement request' of Maemo Bugzilla is good enough.
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