Papas Fritas writes:
"There's an interesting read today by John Paul Titlow at FastCoLabs about DuckDuckGo, a search engine launched in 2008 that is now doing 4 million search queries per day and growing 200-500% annually. DuckDuckGo's secret weapon is hardcore privacy. When you do a search from DuckDuckGo's website or one of its mobile apps, it doesn't know who you are. There are no user accounts. Your IP address isn't logged by default. The site doesn't use search cookies to keep track of what you do over time or where else you go online.
'If you look at the logs of people's search sessions, they're the most personal thing on the Internet,' says founder Gabriel Weinberg. 'Unlike Facebook, where you choose what to post, with search you're typing in medical and financial problems and all sorts of other things. You're not thinking about the privacy implications of your search history.' DuckDuckGo's no-holds-barred approach to privacy gives the search engine a unique selling point as Google gobbles up more private user data. 'It was extreme at the time,' says Weinberg. 'And it still may be considered extreme by some people, but I think it's becoming less extreme nowadays. In the last year, it's become obvious why people don't want to be tracked.'"
(Score: 5, Informative) by Fluffeh on Thursday February 20 2014, @11:59PM
The Wikipedia article states that the revenue is from advertising.
If you perform a search on the site, you will see simple sponsored links at the top of the results. No adwords, no sneaky embedded "paid" search results, just a result in a yellow/orange highlight with the words "Sponsored Link" at the bottom right.
Enough visitors and that's a simple way to make money covering costs.