You can also download and test it out: https://addons.mozilla.org/en-US/firefox/addon/illuminator/

This add-on illuminates the corporate and political power structures of the 1%. Though these ubiquitous relationships are often complex and unknown, the addon reveals the connections between corporations, brands and individuals by clarifying who owns what. It iterates through all of the html text in your browser and whenever it finds a person or corporation from the data,it appends that person, brand or corporation with who they are owned by, sponsored by, or acquired by.

For example, this is an example of what you would see appended to someone's name if they're on a board of a Fortune 1000 company:

Data was compiled mainly from the Little Sis API, lists of lists on Wikipedia, and other media sources.

However, it's very very slow right now (there's a 14000 line regex) and causes lags in the browser. Any help/thoughts on making this faster would be welcome.