Yeah, when people think of oil, they just think gasoline. But there's a huge number of products that come from oil.<quoted text>
Actually, they can't make cars that "run on water," sadly. It's not really feasible for several reasons, most importantly physics. The amount of energy require to break the water molecule into hydrogen and oxygen gas is three times the energy derived from igniting such gasses. It's a fun science experiment but was not effective in the long term, and is less efficient than even our electric cars.
Also, the "big oil company" thing you mentioned is, technically, a conspiracy theory, or as I call it, conspiracy nuttery. Oil companies make more money on plastics and textile production than anything, more factory new computers are sold every year than cars in a decade. Even with our technology recycling programs we use more virgin plastic on computers each year than any other product on the market, in the US and Europe at least. Oil companies also make no money off electricity production now, that's all coal, a different industry.
There are alternatives, the problem is that the lobbyists are all for their own pet corporations, all of them, even the "green" ones, all they want is to push for money into their corporations. One of the huge tax wasters is the raw material recycling companies now, I can go into detail if you want to change topics. But oil companies themselves don't even care about the fuel industry anymore, and while we're working on some great new bio-plastics, we will need the petroleum plastics for at least another century.
At the risk of sounding spammy, I was watching a company called Changing World Technologies (now bankrupt), but here's the wiki page:
They were trying to make oil with thermal depolymerization from waste products at a commercial level.
While not entirely a green type thing, it did have two things going for it - slowing the filling of landfills and easing the pressures of getting oil from abroad.
This is much different than water fueled cars as the company actually did create diesel fuel from discarded turkeys parts.:o
However, the process apparently stinks pretty bad and the plants need to be placed way out of the way. I'm thinking near Dick Cheney, George Bush and oil exec's ranches would be poetic justice.