Find the Best Translation and Improve Google Translate
Google Translate shows a new message at the bottom of the page: "Would you mind answering some questions to help improve translation quality?" It's not a boring survey, it's actually a great way to test your foreign language skills by picking the best translation.
Here's the link, just in case you can't find it. The URL parameters are only for English to French translations, but you can replace "fr" with "es", "de", "it" or other language code.