When I was growing up my parents had a christmas light set that would play music out of this green box:

http://img515.imageshack.us/img515/862/christmasboxqb7.jpg

If I recall correctly it only has a single button on the box to change the lights flash rate and audio level.

This really meant a lot for me as a kid and if anyone knows anything about this box please let me know :)

What were the tunes that would be played out of the box, please? Knowing that, might help people to answer your question.

I only remember two but it had several, one was rudolph the red nosed reindeer and another I think had the word "the lord has come" the did have lyrics just midi songs but ever since I was a kid that's the words I thought went with one of the songs.

This is a really rare find :D

EDIT: Looked at the lyrics and that song was for sure "Joy to the world"