This site is really cool. Thanks for sharing though I'm afraid I'll be wasting quite some time today playing around with it :)

[edit]

It looks like the site doesn't get such a large number of people very often and the CPU load is getting too high to hear anything clearly. For clearer audio of the buzzer check here:

http://websdr.printf.cc:8901/

More web based receivers are also available on http://sdr.hu and http://websdr.org

Neato - it's picking up the buzzer station right now!

If you're unfamiliar, search for 'number station.' They are kinda neat and still in use.