There’s a great example of the impact of a rising trends on companies and regions on the stock research page of Fidelity.com today. You can get to this page here.
First look down on the right hand side – you can see the hot topics rising on the web. Not surprisingly Oil and Gas Ecological Issues is the hottest topic.
What you can now do is click through on the rising topic and see which companies are being impacted by it. Clearly BP and Transocean since they are being held accountable, but also the spill over (!) into positives for alternative energy sources like wind which will benefit companies like GE and Siemens.
Scrolling down on the Fidelity.com research page you can see a long list of interesting articles to read which give you a good in-depth view of which companies are impacted most by the tragedy.