Editor's Note: In this feature from Stockpickr, we highlight lists of stocks that have made new highs, lows or seen other unusual activity.

Biggest % Gainers

: Thursday's market selloff did not stand in the way of

Infinera's

(INFN) - Get Report

initial public offering, as shares rocketed 52% on their first day of trading. The Sunnyvale, Calif.-based chipmaker soared from its offering price of $13, rising $6.70 to $19.70.

Biggest % Losers

: Santa Ana's

SRS Labs

( SRSL) sank 25% Thursday, falling $3.68 to $11.45. Though it's unclear what triggered the downslide, last week the provider of surround sound technology announced the formal award of a patent designed to cover its SRS TruSurround audio enhancement technology.

Rising on Unusual Volume

:

PriceSmart

(PSMT) - Get Report

climbed 12% after the San Diego-based discount retailer said it increased May same-store sales by 21%, with total revenue gaining 22%. Shares traded more than three times average volume, and the stock closed $2.44 higher, at $22.71.

52-Week Highs

:

DynCorp International

(DCP) - Get Report

surged 23% to an all-time high of $20.70 on Thursday, after the defense contractor posted fourth-quarter earnings that shattered analysts' expectations. The Falls Church, Va.-based company also said it expected full-year 2008 profit to more than double. On the news, CIBC World Markets raised its rating of DynCorp to sector outperformer, from sector performer.

52-Week Lows

:

Volt Information Sciences

( VOL) fell 16%, landing at a 52-week low after the staffing-services company posted second-quarter earnings that missed estimates. The company blamed the low results on "timing of certain contracts of the computer system segment's international division." Shares dropped $3.99 to $21.41.

Stocks with Unusual Option Activity

: Los Gatos, Calif.'s

Netflix

(NFLX) - Get Report

was experiencing unusual options activity. Rumors are stirring that the online movie rental company could be taken over by Amazon.com. On Thursday, trading shares elevated 5.9%, or $1.33, closing at $23.93.

Latest Activist Situations

: Karsch Capital, a 9.3% shareholder of

CSK Auto

( CAO), demanded that the company either consider a sale or hire a new executive team, according to a regulatory filing Thursday. Shares closed up 19 cents, or 1%, at $18.22.

Forum of the Day

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Apple's

(AAPL) - Get Report

iPhone release on June 29?

steven k welcomes advice

.

Do You Know the Answer?

daufisland asks,

What is the best pure natural gas bet in favor of higher natural gas prices come September?

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