If it is something you want to spend time doing, then act on it. Your outsider status can be construed as an advantage in that you are less likely to be constrained by unconscious acceptance of the current dogma of the field.
You have less excuses that ever before, and the availability of knowledge and tools is greater than ever before.
If it is not something you want to spend time on, but feel it is truly a 'great idea,' then I would advise clarifying the idea and passing it on to someone you think might be interested in acting on it. The ability to locate these people is greater than ever before as well.
A google query of inurl:.edu topic of interest, and you are essentially searching across all the university departments in the USA.
You have less excuses that ever before, and the availability of knowledge and tools is greater than ever before.
If you want to design a 3D model - http://sketchup.google.com/
If you want to learn more about aeronautics - http://videolectures.net/mitworld_young_corn_garvey_haggerty...
or, Neuropsychological Associations with Social Versus other Media - http://videolectures.net/icwsm2010_counts_ybf/
or, whatever - http://en.wikipedia.org/wiki/OpenCourseWare
If it is not something you want to spend time on, but feel it is truly a 'great idea,' then I would advise clarifying the idea and passing it on to someone you think might be interested in acting on it. The ability to locate these people is greater than ever before as well.
A google query of inurl:.edu topic of interest, and you are essentially searching across all the university departments in the USA.