The other day I came across a useful site called Lyrics Translate, where you can find, submit and request translations of songs. It currently contains translations between a wide range of languages, including English, German, Russian, Turkish, Spanish, Polish and so on, and the site itself can be viewed in a variety of languages. There is also a forum for translators, as well as articles and videos.
So it look like a good place to practise languages you’re learning – you can find songs in those languages, either originals, or translated from other languages, and you could even have a go at translating songs yourself.
I have submitted translations of Cockles and Mussels (Molly Malone) in Irish and Manx – not my own translations admittedly, and just found a song in Breton with a translations in English, French, Portuguese, Russian and Spanish, and a video. There are quite a few other songs in Breton too.