How can i hear people from 15+ metres away?

Question

I need to hear people from 15+ meter's away, like a sound amplifier or something, so i can listen into a conversation, however i cant "bug" the place i need something so i can hear people but go unnoticed, i wouldn't mind headphones, i just cant bug the place and cant make it obvious, know any places i can buy this gear? and could you recommend anything?

Answer 1

If you place a small cone in your ear (like a receiving dish), and a 9 volt battery on your tongue, it will work exactly like an amplifier.

Answer 2

http://www.google.com/search?hl=en&q=sou...

Answer 3

this is a site in australia

not sure where your from but its just as easy to get these from anywhere