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

:

Hoku Scientific

( HOKU) surged 38% after signing a seven-year, $185 million contract with a maker of solar panels. The fuel-cells maker closed up $2.65 to $9.60.

52-Week Highs

:

Ameron

(AMN) - Get Report

jumped 8% to a 52-week high Thursday, after it posted second-quarter results that blew past Wall Street estimates. The Pasadena-based maker of engineered products was up $6.66 to $89.95.

52-Week Lows

: St. Louis-based

Esco Technologies

(ESE) - Get Report

fell to a 52-week low after the company said its fiscal 2008 outlook might be deflated due to a potential "further delay" in supply contracts with

PG&E

(PCG) - Get Report

. Thursday, shares tumbled $9.83, or 21%, to $36.24.

Biggest % Losers

:

IDM Pharma

( IDMI) plunged 27% after it announced investors will buy 7.1 million shares of common stock and will issue five-year warrants to investors to buy about 2.4 million more shares at an exercise price of $4.06 apiece. Thursday shares sank $1.12 to $3.02.

Rising on Unusual Volume

:

Invesco

(IVZ) - Get Report

, trading at 4 times average volume Thursday, increased 64 cents, or 2.5%, to $26.04. The London-based investment services company announced on June 20 that it purchased 50,000 of its ordinary shares. It is intended that these shares will be held in Treasury.

Stocks with Unusual Option Activity

:

NRG Energy

(NRG) - Get Report

was experiencing unusual options activity Thursday. Shares traded up 19 cents, or 0.5%, to $43.51.

Latest Activist Situations

: Shares of

Kraft Foods

( KFT) jumped 6% Thursday on reports from

CNBC

that activist investor Nelson Peltz has accumulated a 3% stake in the company. Peltz is expected to urge Kraft to sell the Maxwell House and Post brands and to improve the Kraft cheese business. Peltz may also push for more share buybacks. Kraft traded up $2.28, reaching $36.74.

Forum of the Day

CoryS asks,

Chevron

(CVX) - Get Report

or

ConocoPhillips

(COP) - Get Report

?

Do You Know the Answer?

The Blackstone Group's

(BX) - Get Report

IPO is finally priced at $31.

Does anyone have any comments or opinions, Steve Goff "Average Joe Investor" asks.

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