Blekko, the perky little search engine startup that lets you customize your search results, is taking the fight against web spam to a new level. It already allows searchers to mark results as spam and keeps a spam clock that counts how many spam pages are on the web (743 million and counting). Now it is about to block content farms like Demand Media’s eHow and Answerbag entirely. The top 20 sites its users have marked as a source of web spam will now be blocked (see full list below).

Concerns are rising that spam is increasingly taking over search results. So much so that Google recently vowed to become more vigilant and downgrade content farms specifically in search rankings.

Now Blekko is going to do one better and ban the worst offenders entirely. Here is the list of banned sites:

ehow.com
experts-exchange.com
naymz.com
activehotels.com
robtex.com
encyclopedia.com
fixya.com
chacha.com
123people.com
download3k.com
petitionspot.com
thefreedictionary.com
networkedblogs.com
buzzillions.com
shopwiki.com
wowxos.com
answerbag.com
allexperts.com
freewebs.com
copygator.com

Your move, Google.

Crunchbase

• BLEKKO
• DEMAND MEDIA

Company: Blekko

Website: blekko.com

Launch Date: June 1, 2007

Funding: $54.2M

Blekko is a search company founded by Rich Skrenta and his core team from previous company Topix and Netscape’s Open Directory. Blekko was founded halfway through 2007 and has already earned itself an angel round from Baseline Ventures and two ex-Googlers.

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Company: Demand Media

Website: demandmedia.com

Launch Date: June 1, 2006

IPO: NYSE:DMD

Demand Media, Inc. (NYSE: DMD) is a leading content and social media company that informs and entertains one of the Internet’s largest audiences, helps advertisers find innovative ways to engage with their customers and enables publishers to expand their online presence. Headquartered in Santa Monica, CA, Demand Media has offices in North America, South America and Europe.

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