Have a sidebar estimate of the cost of implementing the idea. Serves as a tag that can be clicked on and then list all the ideas in the same cost of implementation range.
Inspired by the challenge of having the formula to calculate the value of an idea, as it would have to be an important variable in calculating the value of an idea.
Added service to the platform.
Making ideas and hence the platform more tangible.
It can be even rough estimates - have ranges. For instance: Free, 0 to $100, $100 - $,1,000, $1,000 - $10,000, $10,000 - $100,000, and so on.
The estimate can either be done by the idea poster, or the moderators. It can even be a colective effort, it can even be set out as a vote.
Or at least have the percieved difficulty of implementation. Complexity, time needed would also be cool filtration aspects. Further down the line, the platform could also list all the skills needed for the implementation of a particular idea: CSS, Photoshop, scriptwriting... Or the job titles needed for hiring.
Therefore we would have another filtration aspect for the visitors. Leading into my other idea for a feature of giving propositions for career routes to aspiring entrepreneurs.