Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Hercules Offshore (HERO.DL) dropped as much as 11% today after a rig standing over a ruptured well collapsed.

So what: A fire broke out on one of Hercules's rigs yesterday, and there are now reports that the rig has collapsed and the fire has yet to be contained. All workers were evacuated and there's no evidence yet of oil escaping from the natural gas well, but the company will be on the hook for massive repair costs at the very least.

Now what: This isn't the BP spill of 2010 for a variety of reasons, but it's still not good for Hercules or the industry. It appears, for now, that it's primarily natural gas that's escaping from the well and it's in shallow water so it will be easier to work on than BP's Deepwater Horizon disaster was, limiting both environmental and financial impact. This could be a drag for the company and is definitely a black eye, but it could present an opportunity to buy because it doesn't appear that it will affect earnings potential in years to come, which is the biggest reason to own the stock.