What does a Silicon Valley giant do when it wants to move into a new kind of business? Go shopping, of course!

Storage colossus EMC (NYSE: EMC) acts the mallrat this time, snapping up privately held database analysis vendor Greenplum for an undisclosed amount cash. The acquisition should close in the third quarter, will not affect EMC's earnings per share this year, and creates a new product category in EMC's portfolio. EMC will continue to sell and support Greenplum's current line of products and solutions. There will be synergies with EMC's VMware (NYSE: VMW) buddies, too, because Greenplum's parallel database model likes to run on clusters of virtual machines.

Greenplum brings a couple of nice extras to the table. The customer list features heavyweights of various industries, including both NYSE Euronext (NYSE: NYX) and Nasdaq OMX Group (Nasdaq: NDAQ) for a clean sweep of Wall Street. The highest-profile client is eBay (Nasdaq: EBAY), which uses Greenplum's data warehousing on a truly massive scale to process activity logs. Given EMC's stature in the data storage market, all of these companies are quite likely to do business with EMC already.

And like a toy in your cereal box, Greenplum comes with a little surprise: Unpaid executive advisor Scott McNealy will continue to guide the EMC underling. If the name rings a bell, that's because McNealy co-founded and then led Sun Microsystems until Oracle (Nasdaq: ORCL) bought his baby last winter. Sun was and still is a major rival to EMC in the storage arrays sector, so McNealy is a valuable addition to the EMC family even if he's just playing the role of an unpaid backseat driver.

Greenplum is not a blockbuster deal for EMC, but it goes to show how EMC is thinking outside the box to find bolt-on solutions that can enhance what the company already does. It's certainly a clearer growth-by-acquisition plan than what Cisco Systems is doing these days. EMC looks like a stock that's worth owning.