The Dow Jones Industrial Average (DJINDICES:^DJI) had added 51 points as of 11 a.m. EST. Dow Jones component Microsoft (NASDAQ:MSFT) led its index higher, while tech stocks Hewlett-Packard (NYSE:HPQ) and Groupon (NASDAQ:GRPN) also rallied.

Philly Fed beats expectations
Perhaps helping to fuel the Dow Jones' rally, the Federal Reserve Bank of Philadelphia's manufacturing index came in with a reading of 9, significantly above the 3.8 economists had anticipated.

While the index isn't the most vital measure of U.S. economic activity, as it is confined to a single region, a better than expected reading here is a sign of a stronger than anticipated economy. 

Microsoft continues to move higher
Shares of Microsoft edged up another 1.5% on Thursday, adding to a gain that has already seen shares climb more than 5% this week. Microsoft is expected to unveil its Office software for Apple iPad next week, a product that should boost Microsoft's bottom line significantly in the coming months. That news was originally reported earlier this week, but Microsoft shareholders may be continuing to digest the long-term consequences for a company that seems to be embracing a more mobile-focused future.

Hewlett-Packard plans 3-D printing product
Microsoft's longtime hardware partner, Hewlett-Packard, was also enjoying a solid week, and shares were 2.4% higher on Thursday. Like Microsoft, HP plans to roll out a new product in the coming months.

In Hewlett-Packard's case, it's a 3-D printer. The company has long been a juggernaut in the traditional paper-printing business, but now Hewlett-Packard will look to extend its expertise into the third dimension. Hewlett-Packard's management said it will offer more detail on its plans to enter the market in June, aiming to offer a product for enterprise users.

Groupon remains volatile
Groupon shares were up 2.6% after a research report indicated that the company's business may be doing better than anticipated. Shares of the daily deal giant edged up a bit more than 2%.

ITG Research hiked its Groupon billings forecast, according to Seeking Alpha. The positive trend in billings is a good sign for Groupon's underlying business, as it suggests the company is performing better than expected.

This shift in Groupon shares isn't the most significant of moves. Groupon has been a particularly volatile stock in recent months, hitting a high near $12 in January before cratering last month after a disappointing earnings report. Longtime Groupon shareholders should be accustomed to such volatility at this point.