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: For the second time this week, data storage specialist Quantum (NYSE: QTM) is riding high on a 12% boost to its share price.

So what: The analyst upgrade that sparked last Friday's big move appears to have hit a nerve, as trading volumes in Quantum stock have stayed unusually high ever since. The stock has been on a rampage for the past month or so, and market momentum can carry prices a long way.

Now what: Quantum's trailing P/E ratio of 75 looks extremely expensive, but the forward-looking version of the same metric is a value-steeped 8.4, and it's easy to see how this dichotomy fuels some extreme price swings, as tends to be the case when investors don't know what they're looking at. Like storage rivals Hitachi (NYSE: HIT) and Hewlett-Packard (NYSE: HPQ), Quantum seems like a great value play today. Unlike those behemoths, Quantum is a small cap flying under the radar, which could make it an even tastier treat.

Interested in more info on Quantum? Add it to your watchlist by clicking here.

Fool contributor Anders Bylund doesn't hold a position in any of the companies discussed here. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. The Fool is investors writing for investors.