I have often thought it would be great to have an idea marketplace, where someone could put up an idea and their 'cost' for giving it to someone ("just give me

I have often thought it would be great to have an idea marketplace, where someone could put up an idea and their 'cost' for giving it to someone ("just give me a lifetime subscription to its use and you can have all the profit"). There would undoubtedly be hundreds of issues to be thrashed out, but it could conceivably do a lot of good as well.