Help needed with ideas on intermittent timer circuit

Hi
I am trying to build a small circuit that would be able to trigger an intermittent noise from a small buzzer or similar.
I need to get the duration and timing of the noise to be random without any external influences and the unit to be battery powered.
Any help would be greatly appreciated.

Rgds
Kev

Here are some Interesting Links related to your subject.

http://world.std.com/~reinhold/truenoise.html

http://www.geofex.com/Article_Folders/LFOs/psuedorandom.htm

https://www.electro-tech-online.com/custompdfs/2004/10/5_005.pdf

http://www.epanorama.net/links/oscillator.html#noise

https://www.electro-tech-online.com/custompdfs/2004/10/noisegen.pdf