What's so great about paper cups?? My students make them out of empty pop cans.

Tuesday, November 18, 2008
IPod Speakers Made From Paper Cups and Sticks

Next time you're down at the diner you might try out the CupSpeakers from Dmitry Zagga. His minimalist speaker design consists four paper cups, a couple of toothpicks and an iPod.

It is, as he puts it, an iPod Ghetto Accessory. There's something very right about these cheap horn speakers -- the clean white lines perfectly match the 2003 2G iPod. But we very much doubt the sound would be louder than that from the earbuds alone. On the other hand, they're likely to be a lot better than some passive speaker systems you can buy.

[source: http://blog.wired.com/gadgets/2008/11/ipod-speakers-m.html]

My students are also quite innovative in class ... and they are recycling (kinda) at the same time - as they have made speakers using empty pop cans and earphones / old speakers. What amazed me was that a) they worked and b) they sounded half-way decent.