Polyglot helps you learn foreign languages by translating random words on the sites you visit
UPDATE: Due to the shutdown of the Google Translate API, Polyglot is no longer being maintained. It's been ported to use Bing Translate but due to rate limits the service is relatively unreliable and cannot be guaranteed to work consistently.
Polyglot translates randomly selected words on the sites you visit into a language of your choice, allowing you to learn and practice foreign vocabulary while you browse the Internet. It won't help with grammar or local idioms, but it's a fun way to quickly memorize all of the root nouns and verbs you'll encounter.
*Mouse over the translated word to view the original text
* Adjustable minimum word length to filter out shorter words like "and", "of", "the", and "it", or you can have Polyglot join them to adjacent phrases for more accurate translation
* Translate multiple words as a single phrase
* Translation from English to any Bing Translate-supported language, including English, French, Spanish, German, Mandarin Chinese, Japanese, and Arabic
* Experimental support for non-English starting languages
* Quick toolbar disable button for when you just want to read something in your native language
*Customizable translated word color settings
*Adjustable translation probability settings let you control how many words are replaced
Contact Information: Questions/comments may be directed to firstname.lastname@example.org. Special thanks to Fernando C.V. and Touseef Liaqat for submitting new feature patches for version 0.8.74.