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: Want an up-close look at how crazy Mr. Market can be? Fool, I give you VirnetX (AMEX: VHC), which rose 15%, then gave it all back and then some. Shares of the communications security specialist were down slightly just before the closing bell.

So what: I can’t find a report that explains why VirnetX soared, but it may not matter. This is the eighth-most watched stock in our Motley Fool CAPS database, ranking ahead of such names as Electronic Arts (Nasdaq: ERTS) and Qlik Technologies (Nasdaq: QLIK). Anything can move a stock when it's watched this closely.

Now what: Whatever caused the pop, the euphoria had already come and gone as of this writing. The lesson? As sexy as VirnetX’s stock story is -- what could be better than cashing in on a trove of LTE patent treasures? -- investors are better served sticking to the fundamentals. VirnetX doesn’t have much to work with in that department. Do you agree? Disagree? Weigh in using the comments box below.

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