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 satellite communications technologist ICO Global Communications (Nasdaq: ICOG) experienced heavy volatility in trading today on above-average volume.

So what: Within the first half-hour of trading, the stock suddenly sank as much as 18% on no apparent news, only to quickly recover the majority of that loss. Of course, given that ICO is a relatively small, speculative, and thinly traded penny stock, it's no surprise that it's acting extra crazy on a big down market day like today.

Now what: I wouldn't be so quick to pounce on the plunge. Even with today's weakness, ICO is up about 70% in 2011 and has returned a whopping 355% over the past two years. Paying up for opportunities often makes sense, but given ICO's spotty earnings history, consistently negative cash flow, and highly volatile stock price, conservative investors would probably do well to stay away.

Interested in more info on ICO? Add it to your watchlist.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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