If you buy 4 cans of Pringles in the US or 3 cans in the UK, France and spain (I did not check all the countries but it looks like it's everywhere you can buy Pringles), Pringles will send you a free speaker by mail. The speaker fits the can and the can is used to amplify the bass. The speaker can be use with any portable device that has a 3.5mm jack such as Ipod.
Pringles not only wants to show the "upcyclable potential" of their cans but most of all, they have a great marketing idea by extending the life of their packaging.
Brett Butterworth from Sound and vision decided to improve the sound quality by stuffing the can with recycled denim insulation or fiberglass insulation the same way acoustic suspension speakers are made, and it works! He got rid off the bad vibrations from the can with a much tighter and better defined sound.
Pringles cans can be upcycled in many other different ways, but this will be an other post....