In its fourth straight day of 100-point swings, the Dow Jones Industrial Average (DJINDICES:^DJI) shot up today, as Federal Reserve officials moved to calm the financial world. Wall Street has needed calming down since last week, when the Dow cratered more than 550 points in just two days, as fears spread over easing stimulus efforts. But indications Thursday from several Fed bigwigs that benchmark interest rates won't be rising any time soon soothed markets, and the Dow gained 114 points, or 0.8%, to close at 15,024. Boeing (NYSE:BA) stock again ended as one of the better performers today.

Hewlett-Packard (NYSE:HPQ), however, was the top performer, rising 3.2%. The turnaround tech company just won a 10-year contract with the government of Spain to help manage a shift to the cloud in the name of efficiency and innovation. HP is also trying to redefine itself, shifting its business increasingly from the PC market of yesteryear to the more profitable enterprise services markets of tomorrow. 

Aerospace mainstay Boeing, which was yesterday's top-performing Dow stock, added 2.4% again today, as it continues to win big contracts and gain new business. The company just locked down a joint venture with Lockheed-Martin from the Department of Defense for what could be upwards of $1 billion. The contract funds the development of an Evolved Expendable Launch Vehicle, which serves to thrust satellites into orbit. 

America's largest health insurer, UnitedHealth Group (NYSE:UNH), was another big blue-chip winner Thursday, tacking on 2%. From a valuation standpoint, the stock trades at just under 13 times earnings, even after a nearly 22% run-up in its share price already this year. Investors are piling in to UnitedHealth -- which hit a new 52-week high today -- as Obamacare promises to increase the pool of the insured in coming years. 

Lastly, shares of Johnson & Johnson (NYSE:JNJ) ended as one of just two Dow decliners, slipping 0.3% Thursday. Though there isn't a clear motive behind today's move, the stock has been unusually resilient recently, gaining in each of the previous four trading sessions, and posting 23% gains already this year. Considering the type of conservative income investors attracted by the 3.2% dividend that the health-care company pays, it's understandable that some shareholders may want to take gains before valuations get too heady.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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