@Adrian Well to get to good ideas one just has to throw around ideas and keep going. Like what Ian said Edison played and played with an idea that led to light for homes. This is really about bouncing around business ideas.

I understand critics, many of the ideas that are making people money in the world today are ideas that people say would never work. When I was living in England I went to soho china town, and the place is full of chinese restaurants, how does one then open a another chineses restarant in a place full of chinese restaurants and make a sucess. One owner starts a restaurant called Wonkys, the theme of the chinese restuarant is that the waiters and chefs are very rude to clients, the restaurant is famous for that. What happens in Vagas people still open casinos.

Water Purification
I actually ran a small water purification business and there is money to be made, bottled water is just Reverse Osmosis purified water, one could hire out water dispensers and supply companies with water refils, good money in that. Or better yet sell the water dispensers and supply the water. The water companies need a revamp though, in Reverse Osmosis there is 6 stages of purification, the problem is that in selling the fillters you can buy a single stage filtration but you cant then just upgrade your single to double and so on till you get to the RO stage, if that is done plenty can be made. It does not matter if there is a cheap way of purifying water and there are many. People still buy expensive products.

The Ideas I was putting forth are looking at the downward direction South Africa is taking and where the future of making money is. But this thread is about any ideas and how to make them work.

On education and that I think one could start a time bank. This have been very succesful in many places.

On the Rasbery Pi, I am desperatly looking for one, and I know quite a few others that are, so already I see a market for that, it maybe money to be made in the short run but it is money to be made.