Good article that talks about Google buying company Freebase, a free collaborative database. More interesting is a host of other acuisitions making up a veritable buying spree. Business Insider SAI, the author even offered grades on other acquisitions not listed below.

In past 10 months, Google has acquired 16 different companies. Most of the purchases are small acqui-hires, where Google brings in smart people to make its products stronger.

The list of acquisitions mentioned includes:

Ruba
“Ruba offer users a way to visually browse through cities and their attractions around the world, offering photo-rich guides and an emphasis on making it easy to quickly discover new locations.”

Simplify Media
Allows users to stream music from the desktop to their mobile phone. Google purchased the company and will use the technology to stream music to Android handsets

Episodic
Episodic is a platform that allows its users to monetize web videos by inserting ads. It will join the youtube team.

Plink
Google bought Plink to help its mobile visual search, Google Goggles. With Plink’s application, you can take a photo of a famous painting with your phone, then have information about the painting show up on your phone

Agnilux
Google bought Agnilux, a stealth startup from the guys behind PA Semi, the chip company Apple purchase in 2008. Agnilux was believed to be working on some sort of server technology.

Labpixies
Labpixies makes widgets for iGoogle and Open Social. It will be joining Google’s Tel Aviv office

BumpTop
Bumptop makes cool 3D user interfaces. If there’s one place Google could use help its on user interface. Design is not one of Google’s strong suits. As it does more mobile phones and prepares to build an OS for netbooks, BumpTop could help make these things look decent.

DocVerse ($25 million buyout)
DocVerse makes Microsoft office documents available for multiple people to edit simultaneously from different locations. Google paid a reported $25 million for the company and will fold it into the team working on Google Docs.

Google gets a talented group to help it attack Microsoft’s Office cash cow, while also making needed improvements to Google Docs.

Picnik
As Google builds its own cloud based operating system, and web based applications, a nice photo-editing application will be valuable. It will also help Google improve its photo site Picasa. It might also be a nice defensive move. Flickr uses Picnik, so Yahoo might have been interested in purchasing the company.

reMail
Cool mobile email app that will be refocused on translating Google Mail into the iPhone

Aardvark
Aardvark is a social search tool built by a bunch of people that once worked at Google. If you have a question, you submit through Aardvark which routes the question via a variety of channels to people that could answer it. You can see how Aardvark works here. This won’t be a big business. And it doesn’t fit with Google’s current search offerings. It’s the sort of side-project that should be shut down in 2 years.

AppJet
Etherpad was its product but will focus on Google Wave to assist Google’s Docs business, its operating system and email.

Teracent
Teracent uses an algorithm to improve the creative elements of a display ad. (The lower of these two ads was selected using Teracent technology.)

Eric has repeatedly stated that display advertising is the next big business for Google. Adding a cool display technology to the company makes perfect sense.

Gizmo5 ($30 million buyout)
VOIP company. Gizmo5 is already integrated into Google Voice. Down the road, it could feature heavily in Google’s mobile plans. It could also challenge Skype eventually.

AdMob ($75 million buyout)
Google is an advertising company with big ambitions in the mobile space. This has a lot of promise for Google’s long term objectives. The deal is still being held up by regulatory scrutiny, and we think it could be one of Google’s last big acquisitions for a while. Fun fact about the AdMob purchase: Google is paying $750 million for the company. The total mobile ad market had just $160 million in 2008, according to the Kelsey Group.

reCaptcha
Many of reCAPTCHA’s words come from scanned newspapers and old books. By having humans type the scanned words into reCAPTCHA, they get help reading the scanned text. This could be helpful for Google’s book scanning project.

On2 ($133 million buyout)
Google was really paying for On2’s VP8 codec, which it has open sourced in an effort to simplfy and grow web video adoption.