Stamps.com (STMP) and Zhongpin Inc. (HOGS)

Shares appreciated by 9.35% during the session, while volume for this top performer neared 545,000. Normally, the company musters about 200,000.

The leading provider of Internet-based postage announced "the best quarter in the history of the company" in late July. Second-quarter earnings per share of 39 cents soared past the Zacks Consensus Estimate by more than 116%. The result continues an impressive record of beating quarterly earnings expectations for STMP.

Revenue jumped 26% to $26.6 million.

The company also enhanced its EPS and revenue outlooks for 2011, which had a very positive impact on earnings estimates. The Zacks Consensus Estimate for this year is currently 99 cents per share, which is unchanged in 30 days but up nearly 34% from 2 months ago.

Meanwhile, the Zacks Consensus Estimate of $1.03 for 2012 has advanced practically 20% in that time.

"HOGS" is a pretty apt ticker for Zhongpin Inc. ( HOGS - Snapshot Report ) , a Chinese meat and food processing company that specializes in pork and pork products, as well as vegetables and fruit.

HOGS was living high on the list today as shares gained 7.6%, making it one of the top-performing Zacks #1 Ranks.

Meanwhile, earnings estimates have moved up in the past 30 days following a solid second quarter report from early August.

The Zacks Consensus Estimate for 2011 is up 4.3% in the past month to $1.94 per share. As for 2012, the Zacks Consensus Estimate has advanced nearly 7% to $2.48.

At the moment, analysts are expecting profit growth of around 28% for next year over this year.

For its most recently-reported quarter, HOGS announced earnings per share of 48 cents, which topped the Zacks Consensus Estimate by more than 17%.

Revenues soared 70% to $366.5 million.

The first-half numbers were so good for HOGS that it decided to revise its outlook for the full year. The reaction to this move can be seen in the graph below:

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