I'm sure I'll be put on the cross for this, but I think a true free market system actually does work, completely unregulated in the traditional sense.
In a *true* free market, there are no regulations either way in regards to companies; no weight is given to their requests when the law is concerned. If a product in a free market system is in demand, and a company stands to lose profit from its availability, there should be no law or unbalanced tariffs placed upon that commodity's trade.
You might be thinking "WHOAH, free market with NO regulations? We'd be dead in a week!", but please bear with me. In a true free market system, corporations are essentially thinly veiled; If a product is released that is harmful, and (in treating corporations as a non-affiliated entity) information is requested, and it is denied, or does not bear tests, people will not buy their products. This means that any sneaky skullduggery they don't want the world knowing about is still found out through the denial of the request; if they don't want to fess up, that's on the record and people know to avoid the product(and possibly the company entirely).
Regulation of activity comes from, ironically, the supply and demand system. We're used to this regulating prices on its own- it's a passive package deal, but what about regulating corporate activity?
If the people want something, we can consider this a negative supply. The product exists conceptually at this point; something which does some particular action. Laws of supply and demand dictate that if a company were to provide that product in a situation of high negative supply, that company could stand to make a lot of profit up front, without scalping of prices being necessary to recover initial costs. So the regulation(through interaction) and direction(through needed supply) of the market is the people themselves. Advertising and other commercial activity is important up to a certain point, that point is located on the fine line somewhere between "Reaching every person interested in the product" and "Trying to sell a product to people who aren't interested in it".
Also, a true free market is not without regulation per se; companies can stand to make a business out of testing products and their contents for health hazards and other such issues, or an entity can do this on behalf of the people(government agency, not-for-profit organization, volunteer organization, college, or other such less vulnerable to bribery), denial of requests to test products and facilities are pinned up just the same as a denial of an information request; known to the people, aka the customers.
The most basic rule of business is that if something is in need, make it available and you will have good business. There are a LOT of things in need today, such as better agriculture systems immune to droughts, better roads which require far less maintainence, better vehicles which take less energy but don't lose performance, better renewable technology to reduce resource requirements further. If you listen to what the people are asking for and provide it, you will be well on your way in no time. Don't over-produce, because interest ebbs and flows.
All of these banks and CEOs could've taken their fair pay(instead of excessive bonuses and salary) and invested into these things that are in need and made out exactly the same without the whole market collapse, and without cutting quality, either. But I guess that's what happens when you train your companies in income bubblenautics, and focus only on money as a measure of productivity.
I guess I'm just a no-good no-regulations conservative now, eh?