Slashtags search only the sites a user wants to comb and cuts out the so-called "spam sites." In doing so, Blekko aims to let users slash across the web more quickly than traditional search.

"I haven't done side-by-side comparisons with Google or Bing to see how it performs on similar queries, but this is a very creative approach that makes search different," said Greg Sterling, principal analyst at Sterling Market Intelligence. "Blekko is exposing a lot of information, including SEO-related data , and its algorithm is fairly open."

Customized Search

Essentially, Blekko lets users do something Google does not -- at least at this level -- and that is to customize search results. Users can create a slashtag that includes their favorite sites on any given topic. It can be as narrow or as broad as the user likes. But when the user searches, he or she is only searching those sites. It's essentially a thin slice of the web.

"If you have particular sites you like for certain things, like health queries or movie blogs, you can create a customized index and you can search only that index," Sterling explained. "There is also this social dimension where people will be creating these and you can follow people. So there's a little bit of Twitter feel in there."

The social dimension comes in when you find a friend's slashtag and include his or her customized list of search sites in your own. You might search a friend's sports slashtag for the latest World Series drama, for example.

Realistic Search Expectations

"The social elements and customization make it different from what you get on Bing or Google. Right now, it's kind of a geek or power-user tool," Sterling said. "A lot of people in the mainstream won't see any reason to use it. But people who are insiders or long-time search-engine power users may find some of its features pretty interesting."

That said, Blekko has made it easy for even the search novice to get started, creating hundreds of topic slashtags that users can start with. There are topics dealing with humor, venture capital, UFOs, global warming, and more.

Unlike search upstarts like Cuil, which debuted in 2008 claiming to combine the largest web index with content-based relevance in a quest to topple Google, Sterling said Blekko has more realistic market expectations.

"Cuil was heavily hyped as a head-on competitor to Google. Blekko doesn't have that same expectation. Their view is they are going to start small and over time hopefully grow their usage," Sterling said. "It's lunacy to build a general search engine at this stage of the game because there are so many who have tried and failed. But Blekko has some interesting ideas and they are creative about it, and they've been very realistic about what they are up against."

Recommended Reading: Search & Destroy: Why You Can't Trust Google Inc. Synopsis: This is the other side of the Google story. In Search & Destroy, Google expert Scott Cleland, shows that the world's most powerful company is not who it pretends to be. Google pretends to be a harmless lamb, but chose a full-size model of a Tyrannosaurus Rex as its mascot. Beware the T-Rex in sheep's clothing.