Want a site with functionality similar to ProTrade.com.
*news (rss feeds, visitor-customizable)
*stock market (this section should work identical to the Auction House on World of Warcraft -- [url removed, login to view]) where people can put in a minimum bid, a maximum bid, or buy out an item at a price set by the seller. one or multiple shares can be sold at once.)
*registration (visitors register for site access)
*inventory (lists inventory of registered users. integrate with RSS feeds above. interface to let users sell their items in stock market as well.)