Platform for OpenSource business solutions

Hi everyone!

I recently (last night, in a dream) came up with an idea:

Creating a website on which volunteer, "opensource-minded" people can propose solutions to any business, invent and discuss new economic models and strategies etc.

Many would argue that this is a very unprofitable way of wasting time (since many people in the world are actually paid for consulting businesses and other administrative elements), but I think this kind of initiative may raise the awareness especially of young people (teenagers, university students) and motivate them to think actively about the world.

What do you think of this? Do similar projects already exist?

Now, my main question is actually: how can I do this?
My last experience with webdesign was based on high graphic design and CSS, and I was out of the technology world during the Web 2.0 boom (blogs, podcasts, wikis, community-platforms, etc.).

Since I expect that the project community will be small, I don't want to create a largescale forum like this one. It might appear empty...
Wouldn't something like a blog be better, on which the different authors can write their articles or business models/solutions, which can be commented by the others?

Which platform do you think is best for this kind of project? I have heard of so many platforms but have no clue where to start... phpBB portal, mediawiki, livejournal, etc.

Thanks a lot in advance