The atacontrol and xset commands are good candidates for adding to /etc/devd.conf.
Everytime you insert or remove the power cable from your notebook, devd gets an ACPI message. (0x00 and 0x01 IIRC). So if you plug-in the cable you can run
Everytime you insert or remove the power cable from your notebook, devd gets an ACPI message. (0x00 and 0x01 IIRC). So if you plug-in the cable you can run
# atacontrol spindown ad0 300 and vice versa if you remove the cable.