November 20, 2008, Updated September 13, 2012

When asked by colleagues or potential business partners, high-tech entrepreneur Gideon Greenspan says he has 25 years of experience as a software developer. Most people scratch their heads, of course: Greenspan, who’s developed the world’s most popular online Sudoku game Web Sudoku, is only 32 years old and he looks much younger than his age.

“I started writing software when I was seven and started selling it when I was 17 in London,” says Greenspan, both an Israeli and UK citizen who now calls Tel Aviv home. While the Macintosh utilities that he created as a teen (covered on TechTV and CNN, among others) still see some online sales, it was Web Sudoku — built with his wife Rachel, a statistician — that really set the world on fire.

After laying the foundations for Web Sudoku, very quickly Greenspan invited his wife Rachel into the project. “She analyzed the puzzles and worked out the logic,” he tells ISRAEL21c. “She understands that side of things a lot better than I do.”

Voted by TIME Magazine as one of the best websites of 2008, Greenspan’s game sees about 250,000 users a day, and is syndicated by American newspapers such as the Chicago Sun Times Online and The Denver Post and the online portal Yahoo. The website is surprisingly simple and clean, with basic puzzle choices in levels of easy, medium, hard and ‘evil.’

Copyscape for catching content thieves

Since founding Web Sudoku in 2005, there have also been premium Sudoku downloads for Mac and PC, and a series of Sudoku puzzle books, with the most popular ones sold in Germany. But Web Sudoku isn’t Greenspan’s first online success. A year earlier, he released Copyscape, a plagiarism search engine that can track down copies of content and where it’s published online.

Helping writers, newspapers and website owners, Copyscape keep tabs on where their printed copy is going and offers both premium services as well as free searches. Launched in 2004, it is currently used by about 200,000 content owners every month.

The original Google Alert

Other smaller enterprises created by Greenspan include Google Alert, launched in 2003 before Google came out with its own alerts, and one of the first applications of Google’s original search API. Over 200,000 people have subscribed to the service, for the in-depth results it provides above and beyond Google’s offering.

Premium services, advertising and syndication sales for Web Sudoku, Copyscape and Google Alert, have allowed Greenspan to develop in a new direction, and today he’s devoting his spare time and then some, to the environment.

“I’ve always been aware of green issues. One thing I like about the software business is that you can create a lot of economic value while consuming (relatively) few natural resources. But I’m no “tree hugger” and my approach is pragmatic rather than ideological.”

Carbon Catalog for the environment

In response, Greenspan has built Carbon Catalog, the world’s most comprehensive and up-to-date source of where to buy carbon offsets, the carbon credits people and companies purchase to offset the greenhouse gas emissions created by taking flights, driving cars or consuming food and energy.

“While there were tons of providers selling offsets online, I was looking for a central repository of information that compared and contrasted the providers, so I could make an informed choice about where to buy,” says Greenspan.

“Eventually I decided to solve the problem myself, and created Carbon Catalog. Carbon Catalog is a directory of carbon-offset providers and the projects that they support. The listings are regularly updated based on the information on each provider’s website. Carbon Catalog also rates providers based on their transparency and the quality of their projects.

“But there’s also an entrepreneurial angle. Depending on what happens in the UN, and in America’s corridors of power, the next decade could see massive growth in the carbon markets, and I’m positioning Carbon Catalog to take advantage of that. But this is for the longer term – for now, I’m focused on providing a non-commercial service for voluntary offset buyers.”

Greenspan also advises a number of Internet companies on technology and strategy. He has a PhD in Computer Science from the Technion – Israel Institute of Science, and two MAs — in Philosophy and Computer Science — from the University of London and Cambridge.

A few words of wisdom for those who’d like to build a high-tech company? “I follow the Google formula,” says Greenspan. “That’s doing one simple thing as well as you can, and not bothering users with too many adverts or other distractions. The other running theme in my strategy is that I pursue ideas that don’t require excessive upfront investment.

“I tend to do things differently and grow along with my projects.”

*Photo by Rick McCharles

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Jason Harris

Jason Harris

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