Amazon.com (Nasdaq: AMZN) just keeps getting better. The e-tail giant has just announced that it's acquiring Kiva Systems in a $775 million cash deal, which is expected to close in the second quarter.

Kiva makes small orange robots that are deployed within shipping and fulfillment centers to boost productivity and offer a "complete order fulfillment solution" that does a handful of tasks. These little brightly colored fellows are already in use by two of Amazon's other websites, Zappos.com and Diapers.com.

Source: KIVASystems.com.

They complement humans by bringing shelves loaded with products directly to workers, while using a laser pointer to help direct the worker to which product needs to be picked out and packed into an order. Kiva estimates that it can boost productivity by as much as three to four times.

This is the second-largest acquisition that Amazon has made, topped only by the Zappos.com deal in 2009 for nearly $900 million. Also high on that list was the roughly $545 million deal to acquire Quidsi, which brought Diapers.com and Soap.com into Amazon's fold.

On top of that, Amazon has confirmed that it's not planning on hogging these machines for itself. It will continue selling the technology to other retailers. Gap (NYSE: GPS) is among the brick-and-mortar retailers that tap into Kiva's automatons, so it won't be left out looking for a substitute.

This is what I like to see as an Amazon shareholder: aggressively investing in future growth by beefing up infrastructure. Short-sighted investors have been disappointed with Amazon's falling bottom line, but its growing top line encourages me.

On the digital side, it continues to beef up its Google (Nasdaq: GOOG) Android Appstore, leading the Android tablet pack even though it marches by the beat of its own drum. Its Prime Instant Video catalog continues to grow and keeps Netflix (Nasdaq: NFLX) on its red toes.

All signs are pointing to a bright future with Amazon.

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