InterOil ( IOC) was one of Friday's small-cap winners as the Canadian oil company with operations in Papua New Guinea said it was encouraged by early test results at the Elk #1 discovery well. Shares were trading up $1.75, or 10.6%, to $18.30.

Omnicell ( OMCL) gained after the Mountain View, Calif.-based company, which makes medication-dispensing systems, said third-quarter earnings doubled. The company earned $2.8 million, or 10 cents a share, up from $1.4 million, or 5 cents a share, a year ago. Revenue totaled $40.9 million, up 33.4% from a year ago.

Excluding items, Omnicell earned $4.9 million, or 17 cents a share, compared with $1.4 million, or 5 cents a share, a year ago. Analysts polled by Thomson First Call were expecting earnings of 15 cents a share on revenue of $39 million. Shares were trading up $1.58, or 8.8%, to $19.58.

Insteel Industries ( IIIN) posted a fourth-quarter gain, but the Mount Airy, N.C.-based concrete-reinforcing products company slumped after warning of tough business conditions in the future. The company reported earnings of $10.1 million, or 55 cents a share, compared with $6.4 million, or 34 cents share, a year ago. Earnings from continuing operations came to $9.5 million, or 52 cents a share, compared with $6.4 million, or 34 cents a share, a year ago. Revenue slipped 5% to $82.5 million.

Looking ahead, H.O. Woltz III, president and CEO, said in a statement that "we expect business conditions during the first half of 2007 to be less hospitable than in the prior year due to the downturn in housing-related markets and higher cost raw material purchase commitments that may be difficult to recover depending on competitive pricing pressures." Shares were falling $3.46, or 15.8%, to $18.48.

U.S. Concrete ( RMIX) tumbled after the Houston-based company cut its third-quarter guidance due to disappointing sales. The company now expects earnings of 28 cents to 30 cents a share, down from an earlier forecast of 31 cents to 36 cents a share. Wall Street is looking for earnings of 34 cents a share. The company is scheduled to release third-quarter earnings Nov. 9. Shares were falling 93 cents, or 12.9%, to $6.26.

Stamps.com ( STMP) was hammered as the Los Angeles-based Internet-based postage company warned on its full-year outlook. The company posted earnings of $4.3 million, or 18 cents a share, up from $2.6 million, or 11 cents a share, a year ago. Excluding stock-option expenses, the company earned 21 cents a share. Revenue totaled $18.9 million, up 24% from a year ago. Analysts were looking for earnings of 19 cents a share on revenue of $20.8 million.

The company said it expected fiscal 2006 earnings of 64 cents to 67 cents, or 75 cents to 78 cents, excluding stock option expenses. Revenue is expected to total $82 million to $85 million. Analysts are calling for earnings of 78 cents a share on revenue of $87.1 million. For fiscal 2007, Stamps.com also guided below estimates. Shares fell $3.99, or 17.7%, to $15.77.

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