I keep telling you how semiconductor designer Atheros (NASDAQ:ATHR) looks primed for massive returns. Well, the stock has risen more than 40% since my last reminder -- and the company is proving beyond reasonable doubt that it's worth every penny.

Atheros' second-quarter report showed 28% sequential sales growth to $112.2 million and much stronger pro forma earnings that clocked in at $0.20 per share, a significant bump from the $0.06 per share seen last quarter. The company's wireless-communications chips can be found inside every Nintendo (OTC BB: NTDOY.PK) DSi gaming system and in Garmin's (NASDAQ:GRMN) oft-delayed Nuvifone, as well as in countless handsets from Motorola (NYSE:MOT) and others.

Atheros, seeing a massive growth opportunity for its technology, predicts a market of more than 1 billion networked mobile consumer gadgets sold every year. In one specific consumer market, Wi-Fi-enabled cellular handsets, a longstanding collaboration with Qualcomm (NASDAQ:QCOM) gives Atheros a free ride into many new designs. Furthermore, the netbook concept lives and dies with network connectivity, so the rise of that platform is another growth vector for Atheros. The company is also a member of the Open Handset Alliance, meaning that if or when Google's (NASDAQ:GOOG) Android smartphone/netbook software takes off in any meaningful volume, Atheros will be along for the ride. And I think it will.

If that wasn't enough to recommend this longtime Motley Fool Hidden Gems pick, Atheros is sitting on the prettiest balance sheet you'll see this side of Apple (NASDAQ:AAPL). Quarter after quarter of solid income adds up to $492 million of shareholders' equity in $604 million in total assets. Cash equivalents are a very comfortable $340 million, thanks to years of predictable cash flows.

I'm kicking myself for not taking a real-money position six months ago, when the signs of a huge bounce became obvious to me. Darn that Foolish disclosure policy! Note to self: Stop writing about Atheros so I can invest in it instead.

Further high-octane Foolishness:

Google is a Motley Fool Rule Breakers recommendation. Apple and Nintendo are Motley Fool Stock Advisor selections. Garmin and Nintendo are Motley Fool Global Gains recommendations. The Fool owns shares of Atheros Communications, which is also a Motley Fool Hidden Gems recommendation. Try any of our Foolish newsletter services free for 30 days.

Fool contributor Anders Bylund owns shares in Google. Regrettably, he holds no other position in any of the companies discussed here. You can check out Anders' holdings or a concise bio if you like, and The Motley Fool is investors writing for investors.