I've been working on some software for a while. The idea was a search engine which answered questions directly, rather than sending you to a page with the answer.
I'm giving up now and hope to make some cashmoney using the algorithms elsewhere, since I've just had a play with Wolfram|Alpha. The primary test which I have been basing my idea on was asking what the weather is today and getting a straight answer. Wolfram isn't perfect but it passes the test.
As an aside, I asked it to compare the population and GDP of the UK and France. Try it yourself and look at how France has much less money per head than us. Then ask yourself why France is capable of building planes, spacecraft, rockets, trains, nukes, subs, helicopters and just about everything non-trivial that the UK now is only capable of buying from abroad. A little bit of politics there but since the MP's allowances have been made public I've been wondering where the supposed vast riches of the nation are going - not to imply that it all goes on moats and biscuits, of course; the total allowances for every MP might only pay for a feasibility study to put some traffic lights on a B-road in rural Wales.