<p>Looking for a way to read the unique ID / serial# of a USB thumb drive;
please note that<br>
- I am looking for the value of the manufacturer, not the one Windows allocates for it.<br>
- I need to support multiple OS (Windows, Unix, Mac), thus needs to be a Java solution</p>

<p>The idea is to be able to distinguish between different USB thumb drives.</p>

I've never tried using it (it's been on my todo list for a good few months now), but there is the "marge" project on java.net:
http://marge.java.net/
This should let you connect to bluetooth devices (although I don't think it is 100% feature complete, there is demo code on there), and then the ClientDevice class has a "getBluetoothAddress" method which I
believe
should be unique to that device
http://marge.java.net/javadoc/v06/marge-core/net/java/dev/marge/entity/ClientDevice.html
As I say though, I've never tried it...