DuckDuckGo
What makes DuckDuckGo unique is that unlike Google, DuckDuckGo doesn't track your clicks across the Web. So if the government were to come knocking on DuckDuckGo's doors, seeking information, they would have no way to tie that information to individual users.
DuckDuckGo launched back in 2008 as an alternative to traditional search engines that don't respect your privacy. DuckDuckGo CEO Gabriel Weinberg has mostly bootstrapped DuckDuckGo, but he also received $3 million from Union Square Ventures, Scott Banister, Peter Hershberg, Joshua Stylman, Joshua Schachter, Kal Vepuri, and Jim Young.