First, people do talk about healthcare costs and education costs and housing costs as grand problems.

And startups can do something about those. For example:

1. Co-Abode.com which connects single moms to share houses , while getting cheaper prices and better support from each other.

2. A recent YC startup , which helps people who are getting a divorce, settle without lawyers in a relatively peacefull and much cheaper process.

3. All those new education startups who make college more affordable.

And there are plenty more , and plenty more that's could be done. One such example:

Making dental crowns is costly. There are some few large companies who built a small cnc machine who automates this, which can reduce the costs of the whole process by a lot. But they are expensive to acquire.

Find a way to make this available for cheap for every dentist in u.s./world.

Now the question is how does get into those opportunities ?

Well, i don't think it's hard. just focus on the right area , and try to join the communities which try to think about those things. I'm pretty sure they are willing to share problem and ideas in order to see solutions being made.