Brief

Alexadex is a mock stock market where players buy and sell shares of websites. The prices of websites and the amount of shares for sale is determined Alexa's traffic rankings.

New players are started off with $10,000 of play money which can be used to invest in websites. As a website's popularity grows, the price of each share rises and all investors of that site earn play money. If a website's popularity falls, however, the price of each share will drop and investors of that site will lose play money.

As per Alexadex:

A site's share price is set at the either yesterday's daily reach per million or the seven day moving average, which ever is higher, as reported by Alexa site info.

The total shares available for a site is set at the 100 times the log of pi times the 3 month average reach.

Captcha

Alexadex uses a system called captcha to prevent users from using a scripting language. In this system, a user must plug random letters into a box so that the system recognizes it as a person, and not a script.
If a user types an incorrect captcha phrase, they cannot purchase the stock.

Tips & Tricks

1. Look at the traffic graphs for each website you are querying and only buy shares if it appears to be on a low. This way when it does eventually rise it should rise by quite a bit. This is when you should sell it.
<br>2. If you know of games or hot gossip that has a very close release date to the current date then it is often a good idea to purchase shares on the games (etc) homepage.
<br>3. Don't worry if site lose value, they may come back up at some point. In most cases keep hold of them.

External links

Alexadex.com

Alexadexer.com Forum

Explanation of Alexa Traffic Rankings