Ask your students to imagine that they are stranded on a desert island with only their MP3 player for company. The catch is that the MP3 player has had all of its songs erased apart from 10. Your students must note down which 10 songs they would like to remain, and why. Go around the class asking students to explain their choices and encourage other class members to comment on their choices. Do they agree/disagree and why?  If you feel that 10 songs is too many reduce the number appropriately.