Alexa, Amazon's Most Flawed Idea
Alexa doesn't rank itself but you can chek their stats at adbrite site
they get just over 5000 visitors a day, I don't know how many people installed their toolbar but they must be multiplying visitor numbers and traffic stats like crazy. With such a low user base the ranking stats they have can't be very accurate.
I have couple of sites and on that gets twice more visotrs, according to my server logs, is ranked way lower on Alexa the the other.