Enron

(ENE)

was again heavily traded after the regular session closed Thursday following another day in which holders of the company's common stock saw their investment tumble even closer to zero.

The energy merchant ended regular trading at 36 cents, and the issue held that level in action after the close. Enron was the most actively traded stock on Instinet and was also in the top three on the Island ECN.

Nvidia

(NVDA) - Get Report

was off 0.4% to $53.40 in the late session after ending regular trading up 4.4%. The company is joining the S&P 500, replacing Enron. Nvidia was previously a component of the S&P MidCap 400.

Internet Security Systems

(ISSX)

, which is taking the graphics processor maker's slot in that index, was up 0.5% to $32.81 in extra trading.

Cisco

(CSCO) - Get Report

was inching up 0.2% to $19.93, and

Intel

(INTC) - Get Report

was tacking on 0.4% to $32.44.

Pharmacyclics

(PCYC)

was among the volume leaders for the third consecutive session, but was again unchanged from the closing price, this time at $27.

Novell

(NOVL)

was one of the extra session's biggest winners, climbing 8% to $4.31. After the close, the company posted fourth-quarter earnings, excluding items, of 2 cents a share on revenue of $308 million. For the first quarter, the company forecast revenue of $265 million to $275 million, which would probably lead Novell to break even before any items were factored in. The company's results in the latest quarter beat estimates by 2 cents, and the outlook would also top analysts' expectations.

Tellabs

(TLAB)

was also higher after the bell, gaining 2.3% to $15.86. On Island, the

Nasdaq 100 Tracking Stock

(QQQ) - Get Report

was unchanged at $39.94.