Wednesday's Late Winners & Losers

Stocks tip-toed lower after the closing bell Wednesday, but a number of tech names were on the rise -- among them, Sun Microsystems (SUNW Quote).

The Santa Clara, Calif., computer-products maker climbed 3.5% to $5.30 after saying it will buy back up to $3 billion worth of its shares. Likewise for fellow tech name MEMC Electronic Materials (WFR Quote), which announced a $500 million share-repurchase program. Missouri-based MEMC, which makes materials for semiconductor manufacture, recently traded up 92 cents, or 1.6%, to $60.10.

Computer giant Hewlett-Packard (HPQ Quote), of Palo Alto, Calif., came in a penny over Thomson Financial's per-share estimates with fiscal second-quarter income of $1.92 billion, or 70 cents a share. Revenue, at $25.53 billion, was a hair over targets. Shares gained 0.9% to $45.60.

Tech stocks were also prominent on the downside, however. Opnet Technologies (OPNT Quote), a Maryland-based management-software developer, slid 10.4% after fiscal fourth-quarter income totaled $1.6 million, or 7 cents a share -- 2 cents short of expectations. Shares lost $1.25 to $10.75 in recent after-hours trading.

Online music purveyor Napster (NAPS Quote) sank 4.9% to $3.88 after estimating next-quarter sales of $31 million, which is $3.5 million below consensus, even though the Los Angeles-based company bested the Street's loss predictions for the quarter ended March 31.