An email that contains an mp3 file attached. It is usually sent by men trying to win over a girl, or apologizing via song.
Becky: Hey, what's up with you and Ron?
Sam: We were going through a rough patch, but then he sent me "Listen to Your Heart" by DHT. So I forgave him.
Becky: I don't know what's worse, the fact that he sent you gleemail, or the fact that it worked.