We worked on something just like this years ago (over 10 years ago) at an engineering internship I had at an automotive supplier in Michigan. We had a whole mock-up for an auto show. We put directional microphones in a rear-view mirror and sent the signal through an amplifier to the car speakers. The biggest problem we had to overcome was feedback. It is really hard to amplify someones voice in such a small, enclosed space without horrendous feedback, and feedback at all kinds of audio frequencies. I remember we bought this off-the-shelf commercial feedback killer and mounted it under the dash just for the demo and it even had a hard time killing all the feedback.

Two young men in steubenville rape a young women and get 1 - 2 years in jail. A man writes a script to get email address from a website and gets 3.5 years in jail. Something's not right.

All of the charities will end up paying out big bucks in chargeback fees. It is the merchants that are on the hook for credit card fraud. They'll be forced to return the money and pay a chargeback fee ($30 or more). They will end up doing more damage than any potential (and misguided) good.