I was reading through a discussion thread on a programming forum, where someone was proposing that a large software vendor should pay community members for ideas on how to enhance said software vendor's platform. This is an interesting idea, which files in the face of my own personal belief that ideas (with a few notable exceptions) are worth approximately nothing. It is the implementation/execution of the idea that is worth something. Lets look at some big software companies - Microsoft and Google. Operating systems were certainly not a new idea when Microsoft released MS-DOS, it was their implementation of the idea and the royalty stream they created through savvy licensing to IBM that made MS. The operating system they licensed to IBM wasn't even theirs, it was a CP/M clone they bought for $50K. Internet search and on-line advertising were not new ideas when google entered this market, but their dogged refinement of their search implementation built the brand/trust in the company, which in turn lead to extreme user buy-in and eventually a strong “network effect” between on-line content providers (AdSense) and advertisers (AdWords). Strong implementations of ideas are bought and sold every day (they're called companies, or the rights to products) whereas there is not currently an established market for ideas.
See also: No One Is Going To Steal Your Brilliant Idea