Lijit is a "socially aware" search engine:
When your readers search for information in real life, their first step is to typically seek out a friend for the answer. If their friend doesn’t have the answer they need, someone in that friend’s social network may. Eventually, they get an answer they trust, because it came from a source they trust. Your readers can now have that same experience on the web and it all starts with the source they trust. That source is you, the blog publisher.
Lijit allows you to easily create your own search engine, which searches your blog, bookmarks, photos, blogroll, and more. By offering the Lijit Search Wijit on your blog, readers can search all of you. In turn, Lijit gives you detailed statistics about those searches, so you can better understand and serve your reader community.
Update: The Google strikes back