Just a couple weeks after the fiscal cliff negotiations finally bore fruit, Washington has once again pushed its nose into Wall Street's business, this time with some opening salvos in what could become another contentious debate over the debt ceiling. With the President demanding a speedy increase and the Treasury Department ruling out such outlandish solutions as a trillion-dollar platinum coin and other dubious quick fixes, investors largely believe the U.S. won't default on its debt.

But that didn't stop lawmakers from taking the country to the brink of default the last time around, and that may have helped contribute to the broader stock market's losses today, even as the Dow Jones Industrials (^DJI 1.18%) bucked the trend and finished up 19 points.

Within the Dow, Hewlett-Packard (HPQ 0.86%) soared almost 5%. News that rival Dell (DELL.DL) may become the subject of a private equity bid helped boost HP's shares as well. Moreover, even as PC shipments fell again, HP took back the top spot in the industry from Lenovo, after having lost it during the third quarter. HP's gains have only made a small dent in the losses it suffered last year, but the stock has substantial momentum and could see further gains unless fundamental bad news emerges about the company.

Elsewhere, Sears Holdings (SHLDQ) picked up more than 9% after chairman and CEO Eddie Lampert invested about $13.5 million in Sears shares through open-market purchases. Despite the inherent confidence that a stock purchases shows, Sears hasn't demonstrated its ability to engineer a lasting turnaround in its retail business. The question may soon become whether Sears assets can fetch anything closer to their fair market value in an orderly liquidation, and today at least, investors seem to think the answer is yes.

Finally, Molycorp (NYSE: MCP) rose 3.5% in the latest of its volatile movements recently. With rare-earth metals prices having plunged, the big question for Molycorp is whether prices will recover in the near future, or whether a supply-hungry buyer may end up taking over the company to secure a more dependable source of the metals. Without action soon, Molycorp could sink under the weight of substantial debt and negative margins.