Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

You know the old saying, "Sometimes no news is good news?" That pretty much sums up the day for the broad-based S&P 500 (SNPINDEX:^GSPC).

With a big week of economic data on tap with our weekly look at mortgage origination data on Wednesday, weekly initial jobless claims and November's retail sales data on Thursday, and PPI data on Friday, the S&P 500 and traders took a breather today. This allowed the bullishness of recent economic data to send the index to a modest gain, and a fresh all-time closing high.

If you recall, late last week, the unemployment rate dipped to just 7% on stronger-than-expected nonfarm jobs growth, while U.S. GDP motored higher for the third quarter by 3.6%, also much better than economists anticipated. This data appears to signify that the U.S. economy is on healthier footing than many have suspected, and would lend credence that this rally higher could continue.

By day's end, the S&P 500 ended higher by 3.28 points (0.18%) to close at 1,808.37, marking its second day in a row of gains.

Topping the list of gainers today, and bringing back memories of "merger Mondays" in the past, is gastrointestinal diagnostic device maker Given Imaging (UNKNOWN:GIVN.DL), which you probably know best for its camera pill that allows doctors to diagnose gastrointestinal disorders. Given Imaging soared 27.1% after agreeing to be purchased by rival Covidien (UNKNOWN:COV.DL) for $30 per share in cash. The deal will help bolster Covidien's existing line of GI medical devices, and should be earnings accretive for the company by 2015. The purchase price isn't cheap by any means, but it should help bolster Covidien's currently pedestrian growth rate. Although Given Imaging ended the day above the purchase price, I personally wouldn't expect to see a bidding war, with the buyout price an already generous $860 million.

Sticking within the health-care sector, Prana Biotechnology (NASDAQ:PRAN), a clinical-stage biopharmaceutical company focused on developing therapies to treat neurological disorders, saw its shares rise 16.5% after announcing the end of the treatment phase of its Alzheimer's diseases study involving its drug PBT2. Out of the 42 patients enrolled, 40 finished the treatment, for a retention rate of 95%. This included five separate meetings with an independent data safety advisory board, which recommended Prana stay the course each time. Alzheimer's has been a tough disease to crack because of the difficulty to penetrate blood-brain barrier, but Prana may indeed have the inside track. It's a small-cap biotech worth watching.

Finally, coal producer Alpha Natural Resources (OTC:ANRZQ) advanced 14.6% after announcing the sale of a portion of its Marcellus natural gas shale joint venture for $300 million in cash and stock to privately held Rice Energy. Rice and Alpha Natural co-owned the joint venture, which was begun in 2010, but Alpha Natural has struggled with high debt levels and weakened coal prices, thus turning to asset sales in order to boost existing cash on hand. The deal is expected to be completed next year after Rice Energy goes public (as the deal is funded, in part, by $200 million in Rice Energy's common stock). With $2.35 billion in net debt as of last quarter, I'm not too sure I'd be jumping for joy just yet; but at least it's a step in the right direction for Alpha Natural Resources.