Friday was a relatively quiet trading day, with the Dow Jones Industrial Average (DJINDICES:^DJI) up less than a point as of 11:40 a.m. EST. A few stocks, however, were notable outperformers, including Dow component Cisco (NASDAQ:CSCO), BlackBerry (NASDAQ:BBRY), and Sprint (NYSE:S).

A quiet economic day
The Dow's muted move on Friday made sense in light of the sheer lack of economic releases. Besides natural-gas storage figures, the only other economic release was the ECRI Weekly Leading Index, a measure of economic activity in the U.S. That report showed a gain of 1.9%. But it should be noted that it's not a particularly important economic indicator -- economists generally don't provide an estimate for it in advance. 

Cisco outperforms the Dow
Dow component Cisco was a notable outperformer on Friday, rising about 0.5% in a muted market. There didn't seem to be any solid news to explain the move -- no analyst changes, major news announcements, or releases -- but traders were buying Cisco all the same.

Overall, Cisco has had a fairly disappointing year, rallying just more than 11.6% -- far short of the overall market's rise. It's possible that some investors were snatching up Cisco shares in anticipation of the New Year, planning a "Dogs of the Dow" portfolio. The popular investment strategy recommends buying the Dow's 10 worst-performing stocks, then holding them for a year. In light of Cisco's notable drop since November, the networking giant is now one of those 10.

BlackBerry bounces on Lazaridis sale
BlackBerry shares are also higher, but the Canadian handset-maker has gained a much more impressive 4.7%. The gain may have come amid reports that Mike Lazaridis, one of the company's founders, had sold some of his holdings. The Wall Street Journal reported that analysts were reacting positively to the news, as Lazaridis had said he would no longer attempt to purchase the company.

With Lazaridis out of the way, it lets BlackBerry's new management team focus on its planned turnaround strategy.

Sprint continues to surge on merger speculation
While BlackBerry's rally was impressive, Sprint's was even better. The U.S. telecom giant jumped as much as 8% early on Friday amid reports that the company could soon merge with rival T-Mobile. Japanese giant SoftBank owns the vast majority of Sprint and is said to be preparing the financing to acquire T-Mobile. If Sprint and T-Mobile were to merge, it would create a powerful third player in the U.S. wireless industry.

Still, the deal is far from finalized, and a number of questions remain. U.S. regulators could block the deal, and there could be technical issues with unifying the two rivals' services. Sprint is a CDMA network, while T-Mobile uses GSM. Nevertheless, investors appear to like the possibility.

Sam Mattera has no position in any stocks mentioned. The Motley Fool owns shares of International Business Machines. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.