"DuckDuckGo is a new search engine focused on relevant results
and respecting user privacy. Actually a mash-up of several other
sites like Wikipedia, About, Bing, and Yahoo, DuckDuckGo also uses
it's own web crawler: the DuckDuckBot. DuckDuckGo uses what it
calls Zero-click search results to try to guess what you are
looking for and give it to you directly in your search results.
I've been using DuckDuckGo for a few weeks now, and I'm impressed.
What further impresses me is that the entire site is built on open
source tools, ranging from FreeBSD for the operating system to good
old-fashioned Perl for the logic."