
I'm sure there are many many cross-language renderings of pop songs; but more significantly, there are many pop songs that use a "foreign" musical idiom and combine it with original work in a local language. Thus you have rap in many languages; opera in many languages; and so on. Popular music unabashedly borrows styles, which is one reason it is so dynamic. It is only because carnatic music is somewhat a specialized niche interest that we do not have much in non-Indian languages; but if a skilled composer took on such a task (as arasi has, above) it would be rewarding to the listener. Cross-cultural melding is a wonderful thing!
For reciprocity, here's an extract from a Chinese opera sung in English: http://www.youtube.com/watch?v=QnV1XbY302E
Another interesting experiment:
Edward Powell playing his "Ragmakamtar": http://www.youtube.com/watch?v=1q8kEpg05jo