Lol, another one of these.
I always encourage new ideas and ingenuity and shit, but 99.9% of the time, the idea has been thought of already, competition is overwhelming, or it's just not worth it. Make sure you really do have a damn good idea and that it's not just you who loves the idea....
A couple months ago, I thought of producing classy/trendy car air fresheners (not the stupid tree that you hang on your rear-view mirror). I figured if I could come up with an air freshener design that looks cool/classy in any car, with a really nice smell to it, people would love it and would buy it only because of it's trendiness. Needless to say, I followed through with the idea for about 2 days before I decided it's not even worth trying.