I love ideas too but different kind of things than you. I study a type of E coli and someone once asked me why I thought there was diarrhea was it beneficial for the host (ie human) or was it beneficial for the bacteria. It's a hard question to answer because you tend to dilute and rinse away the pathogen which is good for the host but the bacteria get disseminated and possibly enter new hosts which is good for the bacteria. So why do we get diarrhea---should we try to stop it or not? Probably not the kind of question that you want especially with the mention of diarrhea everywhere but that's what I study.