I've been using DuckDuckGo since @yegg's first announcement of it (on reddit iirc). The relevance of the results compared to their competitors' has been noticeably improving over the years.

When a search doesn't quite give me what I'm looking for, I prepend !sp on my query (to use startpage.com). I use this less and less and for most things DDG gets me where I need to go.

I'm a huge fan. I'm thankful services like this are available--that respect our privacy. I did have good intentions of contributing to duckduckhack.com but have regretfully not gotten around to it yet.