Recently, Microsoft introduced a translation service at http://www.microsoft.com/language which was internal only.

This site allow you to search online in Microsoft localization glossaries and terminology database for over 70 languages,

download style guides, give a feedback on terminology used in Microsoft products and find pointers to other languages and localization sites in Microsoft.

Moreover, this site includes around 15.000 standard terms with definitions (in English) and millions of string from products such as Vista and Office.

Enjoy!