Pligg is the only one which seems to have some voting features like IdeaTorrent although it looks to be more focussed on voting for stories than voting for ideas.
Perhaps a Pligg user can comment on its suitability as a replacement for IdeaTorrent?
I was thinking that if you added 'voting' to the open source KB software 68KB (http://68kb.com/) then you could use votes to add 'weight' to the KB articles and that would have the same effect.
KB articles would be 'ideas', and users can add comments and vote.
Pligg is the only one which seems to have some voting features like IdeaTorrent although it looks to be more focussed on voting for stories than voting for ideas.
Perhaps a Pligg user can comment on its suitability as a replacement for IdeaTorrent?