Long-term internet archives aka public record.
Free as in speech software as the default.
Data and format portability.
So pretty much anything privacy related.
That is private and irrelevant information, but they keep pestering me about it. Can you make a start up to solve this problem please? i want more privacy. thanks :)
For a good example of this, see http://www.joelonsoftware.com/items/2008/05/01.html
(along that line) The data that companies have about you available to you in a machine readable format. (e.g. your grocery receipts)
Since the former is difficult and the latter is very difficult, I'd just stick to building something they know they want.
How do you know what that is? Ask them. People aren't bashful when their hair is on fire.
One more thing is that what people want (even when they tell the truth) is not necessarily what they will pay for, or at least pay enough to make it profitable. I want a flying car with a high mpg at the price of a regular car. I'd buy a Segway for $500.
The truth is that there are no formulas for creating a hit. It's a matter of persistence and iteration. Create something, see how people like it, make it better/cheaper depending on what they want, keep iterating. Stay focused and execute better than your competition. Of course, easier said than done.
I'm just suggesting that it's easier to scratch the itch they claim to have than to scratch the itch you think they should be claiming to have.
Either way, you have a lot of work to do.