Let's go over some of last week's best and worst performers.
Novatel Wireless (MIFI) -- Up 57 percent last week
Nasdaq's biggest gainer on the week was Novatel Wireless, the company behind the MiFi mobile hotspot. There wasn't any material news driving the stock higher. Novatel did introduce MT 1200, a mobile tracking telematics solution, on Thursday, but most of the stock's gains had already materialized.
Novatel's been rolling in 2015. The stock has closed higher for seven consecutive trading days. The excitement here stems largely from Novatel trying to position itself as an "Internet of Things" play, connecting historically dormant devices to make them smarter.
Novatel shares were hot several years ago, but the stock plunged into the single digits after smartphone makers began incorporating mobile hotspots into their handsets. There may be a second act for Novatel after all.
J.C. Penney (JCP) -- Up 26 percent last week
There was good news out of the J.C. Penney camp, for a change. The struggling department store chain revealed that holiday comparable-store sales rose 3.7 percent. The strong showing through the seasonally potent months of November and December finds J.C. Penney forecasting comps to move 2 percent to 4 percent higher for the entire quarter that ends at the end of this month.
Ambarella (AMBA) -- Up 21 percent last week
Shares of Ambarella moved higher after a bullish analyst note was published on Tuesday. Canaccord Genuity's Matt Ramsay initiated coverage of the maker of chips that power high-def cameras with a buy rating and a $66 price target.
Ramsay feels that Ambarella can grow its business at a 20 percent to 25 percent annualized pace in the coming years just on the strength of its core businesses that include wearable cameras, security surveillance equipment, and auto-mounted cameras.
hhgregg (HGG) -- Down 20 percent last week
Consumer electronics retailers struggled through 2014, and the holidays were rough for hhgregg. The chain warned that comps declined 6 percent this season, held back by a brutal 35 percent drop in its computers and tablets category. Even appliance sales cooled off, flat with last year's holiday showing.
Apollo Education Group (APOL) -- Down 19 percent last week
The online educator flunked out after lowering its guidance. The company behind the virtual University of Phoenix campus warned that online glitches resulted in many enrolled students backing out after being unable to connect to their Web-based courses.
Five Below (FIVE) -- Down 12 percent last week
Shares of J.C. Penney may have moved higher after coming through with a better-than-expected holiday shopping season, but things went the other way for Five Below. The trendy and growing chain of discount stores where everything costs $5 or less announced that comps during the nine-week holiday shopping period rose 3.2 percent. That's in line with J.C. Penney's store-level performance, but Five Below investors were holding out for better.
A day before Five Below's warning, Jefferies analyst Daniel Binder reiterated his bullish stance, feeling that management had set the bar low, and forecasting that Five Below would beat its guidance, calling for a 4 percent increase in comparable-store sales. That's not likely to happen now.
Motley Fool contributor Rick Munarriz owns shares of Ambarella. The Motley Fool recommends Ambarella and Five Below. The Motley Fool owns shares of Ambarella and is short Five Below. Try any of our Foolish newsletter services free for 30 days. Check out our free report on one great stock to buy for 2015 and beyond.