In fact Google is one of the larger contributors to the OSS movement that I personally know of
Then you dont know much
Or maybe could you please indicate some efficient massive text search technology released by Google under some open/free license?
Or maybe some decent OCR program (ocropus+tesseract are years behind what you get for free in windows with any HP multifunction scanner/printer) so that we could convert those millions of tiff's based pdfs to an editable format?
Perhaps you know of some GIS technology from Google, to allow open/free implementations of world modeling?
And please, let's not forget to mention the little support and even smaller cooperation of Google towards key pieces of the open source world, like the kernel, or java.
Google keeps perfectly closed his cashcow technologies, but those very same technologies are build UPON open/free software. That's the taking and not giving the parent poster was talking about.