Not only did Microsoft practically invent the industry-standard interview technique, but it’s grown by about 88,593 employees since the company started in 1975.

The software giant knows how to pick tech candidates with potential by now. And it turns out that much of what makes a good tech employee is also what makes a good tech entrepreneur.

Inevitably, some Microsofties decided they’d rather try to be Bill Gates than work for him. In 35 years, ex-employees have created a bevy of impressive new companies.

We’ve rounded up 15 of the most interesting ones below.

1. Cupidtino

Yes, Cupidtino, the dating site for Apple fans, was co-founded by ex-Microsoft program manager Mel Sampat (oh, burn). According to the site, “Diehard Mac & Apple fans often have a lot in common — personalities, creative professions, a similar sense of style and aesthetics, taste, and a love for technology.”

2. Picnik

Picnik is an easy photo editing website that was recently acquired by Google. The co-founders, Darrin Massena and Mike Harrington, both worked as development managers at Microsoft, where they “took turns managing each other.” CEO Jonathan Sposato also worked at Microsoft as a senior manager in the consumer division. Before joining Picnik, he started a desktop application app company called Phatbits, which was also purchased by Google.

3. DocVerse

DocVerse is a company that was created by ex-Microsoft employees to share documents created on Microsoft software. But it was recently purchased, as so many startups are these days, by Google.

The service allows real-time sharing and editing of Microsoft Office documents. The plan after the acquisition was to “combine DocVerse with Google Apps to create a bridge between Microsoft Office and Google Apps.”

4. Cranium

Whit Alexander and Richard Tait, the founders of the popular board game Cranium, met at Microsoft. In an unusual move for ex-Microsoft employees, they took their startup business offline. The idea was to develop a board game that offered so many activities that everybody would be good at some portion of it. Their success allowed them to put a hefty $77.5 million price tag on the company when they sold it to Hasbro Inc. in 2008.

5. Stack Overflow

Joel Spolsky, a former member of Microsoft’s Excel team, is the co-creator of this popular Q&A site for programmers. He is also the co-founder and CEO of Fog Creek Software, the author a blog that has been translated into more than 30 languages, and has written four books on software development. Technically that’s at least two more startups for the ex-Microsoft team, but we figured he could only be on the list once.

4. Glassdoor

Glassdoor is a database of anonymously posted information about salaries, interviews, and jobs. You can search by region, position, or even by a specific company (there are, for instance, currently 441 Microsoft interview posts, with questions, on the site). Since the only way to get full access to salaries and reviews is to post one of your own, the content is constantly growing.

Robert Hohman, the co-founder and CEO, started his career at Microsoft. Rich Barton, the other co-founder, is also an ex-Microsoft employee. But he co-founded Zillow.com which we’ll cover later in this post.

7. RealNetworks

In 1995, RealNetworks created the Internet’s first audio streaming program, RealAudio. RealAudio led to RealVideo, which is today known as RealPlayer. Founder Rob Glaser worked at Microsoft for about 10 years prior to starting RealNetworks.

8. Symform

Praerit Garg and Bassam Tabbara are another co-founder pair that left Microsoft together. Their company, Symform, provides online storage for small businesses at a low cost by allowing them to trade inexpensive local storage for cloud storage. Data is divided into fragments, encrypted and sent to random nodes in the system. It’s more affordable than traditional online storage companies because there is no data center infrastructure.

9. Hawthorne Labs

Co-founder Shubham Mittal worked for both Microsoft and Google before starting Hawthorne Labs, which earned his company coveted spots on both ex-employee startup lists. Hawthorne Labs’ first product, Apollo, is a newspaper for the iPad that learns what articles and sources you enjoy and helps you discover new content based on your personal preferences and viewing history.

10. Zillow.com

Zillow.com provides a “zillion” data points about real estate, the market for the place you rest your head at night (zillion + pillow = zillow). Users can look up information on 93 million homes as well as search homes for sale, homes for rent, recently sold homes, and mortgage solutions. Co-founder Rich Barton founded Expedia.com within Microsoft in 1994. The other co-founder, Lloyd Frink, also worked at Expedia before it spun off of Microsoft.

11. Valve

Valve is the creator of Steam, the world’s largest online gaming platform. The company also creates its own games. The first one, Half-Life, has been named the “Best PC Game Ever” by PC Gamer on three separate occasions, and has won more than 50 “game of the year” titles. Founder Gabe Newell spent 13 years at Microsoft before founding Valve in 1996. According to his profile on the Valve site, his greatest contribution to Half-Life was his statement, “Cmon, people, you can’t show the player a really big bomb and not let them blow it up.”

12. Corbis

Bill Gates isn’t exactly an ex-employee of Microsoft, but he’s not really an “employee” now either. Therefore Corbis, the image resource site he founded more than 20 years ago, qualified for this list. While Corbis will likely never live up to its older sibling, having offices in North America, Europe, Asia and Australia and customers in more than 50 countries worldwide is nothing to scoff at.

13. iLike

Co-founder Ali Partovi joined Microsoft by way of acquisition when he sold LinkExchange for $265 million in 1998. He founded iLike, a social music discovery site, with his twin brother Hadi, who had also been on the founding team of the company Tellme Networks (also acquired by Microsoft). Nat Brown, a third co-founder, worked for Microsoft but never sold anything to them.

iLike was acquired by MySpace in 2009.

14. Swipely

Swipely, which launched publically just last month, aims to be “an online service that turns purchases into conversations.” In other words, it automatically shares your credit card purchases across your social networks. Founder Angus Davis was acquired by Microsoft along with his first startup, Tellme Networks, in 2007. He left to start Swipely in 2009.

15. Kashless, Inc.

Companies often give discounts to big groups. With Kashless’s Tiprr, you can get the group discount without necessarily knowing the members of your group. Like Groupon, users receive a daily e-mail with local deals. Unlike Groupon, the deal gets better as more people opt in. The company also runs Kashless, the website, which facilitates recycling by hosting posts for free stuff. The ex-Microsoft founder of the company, Martin Tobias, previously founded a digital media services company called Loudeye Technologies.

Taken from: http://mashable.com/2010/09/23/microsoft-employee-startups/

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