Academic discussions of stock markets frequently reference The Efficient Markets Hypothesis; an idea that share prices are fairly valued, their prices reflecting all available information. However folklore such as "Sell in May and go away", which proved prudent in 2007, clashes with this theory.
posted on May 15, 2008 - View this thread

The Motley Fool's new CAPS stock-picking system keeps track of your stock picks and whether they outperformed or underperformed the market. Then everyone's picks are aggregated, weighted by the quality of their past records, to rank individual stocks. Here's how it works. (more inside)
posted on Oct 4, 2006 - View this thread

"Buy Stock in Ipods. Or Da Vinci Codes." Steve Odom's Smarkets is a web-based stock trading game (and market experiment) based on Amazon.com sales rank. (via jayisgames)
posted on Dec 22, 2005 - View this thread

Consensus View
New Yorker columnist James Surowiecki's book The Wisdom of Crowds "explores a deceptively simple idea that has profound implications: large groups of people are smarter than an elite few, no matter how brilliant—better at solving problems, fostering innovation, coming to wise decisions, even predicting the future." Now this idea has been put into practice with Consensus View, a site where you can enter your predictions on stocks, commodities, and currencies, and view the group consensus. (from wsj.com)
posted on Sep 18, 2005 - View this thread