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These automatic domain value calculators are always terrible and very inaccurate. Most of them give values at least 10 times higher than the market price. That being said, from what I've seen this one looks half decent, but I still wouldn't trust the results. Just because it says your domain is worth $10,000 doesn't mean anything...if I buyer offers you $10,000 then you are in business.
It is fun to play around with these, and it's usually nice to see your domains worth so much. I doubt the accuracy, however. Remember, ANYTHING is only worth what someone is willing to pay for it. The ASK is not nearly as important as the BID!!
I got $ 1,100 for my 46 days old domain! I think these tools are good when you are buying an ad, they are helpful for comparing PR, Alexa, links and traffic all on one page