+ Working on a problem that the big company doesn't see that expands the market. Then the acquisition becomes a matter of buying into the market.
+ Working on a corner case in the big company's market and executing better. In this case the acquisition is amounts to buying a feature.
+ Solving a problem for users in a way that obsoletes the big company's fundamental business model. The acquisition amounts to stifling innovation.
+ Just being so awesome that acquiring your company is the only way to hire your team.
Despite arguments to the contrary, thinking about possible exits is a virtue not an ethical failing. Psychic income is great, but it doesn't always pay the bills. On the other hand, the likelihood of a random outsider having a highly useful model of Google's workings to the degree that being bought by Google is a viable exit strategy on day zero are pretty low [though an insider and industry veteran might be another matter].
Good luck.
Honestly, not everyone is trying to change the world. The real world is full of businesses that provide a good living for their owners and their employees.
You can read books and articles about startups all you want, but those books aren't going to make choices for you. You have decide what is right for you and your business.
if people see the value in what your doing and plan on using it, chances are a big company would too.