Our Greasemonkey script mixes Wikipedia content with information from Yahoo! finance. We began with the idea of mixing the historical and relatively static information from Wikipedia with the dynamic, constantly changing information from Yahoo. Due to the inconsistent format of entries in Wikipedia, our script is limited to Nasdaq companies and runs only on those with an Infobox on the right and a Table of Contents box after the introductory paragraphs. Our "Ticker" insert is hooked into the Infobox and the chart and headlines feed are inserted on top of the Table of Contents box. To view some NASDAQ companies, you can start at the NASDAQ 100 Wikipedia page after installing our Greasemonkey script.
The inconsistent format of Wikipedia was the biggest challenge of this project. Our initial idea was to have the script run on the pages of all publicly traded companies. However, there was no consistent way to tell dynamically which pages were publicly traded companies and which weren't. Some have a "Type: Public" entry in the Infobox, but not all. Getting the ticker symbol was another challenge, as the placement of this information was also inconsistent. Finally, formatting the RSS fed of the Yahoo finance headlines was messy.