I believe I have isolated the problem: my X session crashes (on the hardware indicated earlier) when I switch VTs away from X while nm-applet is displaying the little animation it shows when looking for a network. I've also had two crashes when I killed nm-applet (from the command line) while displaying the animation, although that doesn't happen consistently.
(Nothing nm-applet can do should be able to crash X and the computer, so this remains a bug in X, and probably in the driver.) Peace, Dylan
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