In message <20050302081313.GB16663@drowsy.duskware.de>, Martin Husemann writes:
>On Tue, Mar 01, 2005 at 10:21:06PM -0500, Steven M. Bellovin wrote:
>> Two of my machines have USB mice.  On occasion, and without apparent 
>> cause, the system will stop seeing any mouse events.
>
>I have seen mice die that way.
>
>In my case they were optical ones, so you could see if they were "powered" by
>moving them (which should have made them light up). Everytime they stopped
>sending mouse events, they were not powered any more. I've replaced the mice,
>without looking further, and the problem went away. Probably some bad contact
>of the usb cable, and I didn't feel like soldering (which I actually did for
>the same problem happening to a MS freestyle pro gamepad, where I removed the
>cable connector and instead soldered the cable directly on the pcb).

I'm having the problem with two brand-new, high quality trackballs.  I 
don't think it's a cable problem

		--Prof. Steven M. Bellovin, http://www.cs.columbia.edu/~smb