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 trip-advice purveyor Travelzoo (Nasdaq: TZOO) got lost today, falling as much as 14.2% amid very heavy trading.

So what: The stock jumped sky-high two days in a row after a terrific earnings report, and it looks like traders got a wee bit too enthusiastic. All things considered, Travelzoo shares have still gained 16% since the earnings report.

Now what: Of course, oblique rival (Nasdaq: REDF) is soaring as much as 25% today after launching a discount program in India, which might compete to some degree with Travelzoo's fare. That's a stretch for explaining today's price drop, but still something to keep in mind. There's no shame in taking some profits after consecutive double-digit price gains, and Travelzoo has delivered a soul-crushing 350% return over the last 52 weeks.

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