It was a rocky week on Wall Street, with Nasdaq stocks inching lower and the Dow inching higher, but there were plenty of stocks really making some serious moves. Let's take a closer look at five of this past week's biggest scorchers.

Company

April 25

Weekly Gain

SunPower (SPWR -3.87%)

$34.18

28%

ANI Pharmaceuticals (ANIP -0.55%)

$31.24

22%

VirnetX (VHC -0.63%)

$16.02

17%

Cirrus Logic (CRUS 1.08%)

$21.63

14%

Ballard Power Systems (BLDP -2.76%)

$4.17

10%

Source: Barron's.

Let's start with SunPower. Shares of the profitable provider of solar equipment came through with another blowout quarter. SunPower's profit of $0.49 a share -- when Wall Street was only holding out for net income of $0.32 -- shouldn't come as a surprise. SunPower has blown past analyst profit targets by at least 53% in each of the past four quarters. Global demand for solar products is increasing after a recessionary lull, and SunPower's strategy of selling panels as well as completed solar projects is paying off.

ANI Pharmaceuticals has been moving higher since the end of the prior week. There was no public news to trigger the rally on increased trading volume, but Investor's Business Daily did point to the stock's Monday advance by pointing out that the small drugmaker has seen its sales growth accelerate over the past year, going from 15% to 18% to 56% to 98%.

VirnetX moved higher on better-than-expected iPhone sales. To put things into perspective, patent-rich VirnetX was victorious last month in pending litigation against Apple. It was a awarded a royalty rate of 0.98% on Apple products sold in this country with the FaceTime or VPN on Demand features that infringe on VirnetX's patents. It's true that iPad sales were disappointing, but the 17% pop in iPhone units was a pleasant surprise.

Cirrus Logic was another double-digit winner, moving up after the audio-component supplier posted strong quarterly results and issued an encouraging revenue outlook. Northland Capital Markets upgraded shares of Cirrus Logic following the results, boosting its price target from $22 to $27 along the way.

Finally, we have Ballard Power getting all charged up after acquiring more than 800 patents and applications from United Technologies covering transportation and stationary fuel-cell technology. The two companies also entered into a strategic alliance revolving around the licensing opportunities related to the technology. It's a great catch all around for the much smaller Ballard Power.