via boingboing.net
Some bright spark, who saw this idea then went about and made it real. Plagiarism at it's best, but a nice business opportunity. You snooze you loose.
You can now buy these on Etsy as a 4-pack for $4 : http://www.etsy.com/listing/52058857/iphon-end-call-now-sticker-stops-signal
