12/19   How do you override the hardware MAC addr in OS X?  I tried the usual
        ifconfig en0 laddr anotherAddr but besides disabling the interface
        it seems to do nothing.  It no longer receives DHCP message from
        the cable modem.  (Another machine which has anotherAddr as its real
        MAC works just fine so it's not the fault of the isp.)[restored]
        \_ The MAC address is hardwired to your ethernet controller. You
           can't change this unless you're willing to flash a ROM.
           \_ you're an idiot.
        \_ The following seems to work for me:
           sudo ifconfig en0 down
           sudo ifconfig en0 ether XX:XX:XX:XX:XX:XX
           sudo ifconfig en0 up
           \_ Some sites I went to after googling said the same thing, but
              the second ifconfig gave me
                        ifconfig: ioctl (set lladdr): Network is down
              and refused to change the lladdr.  I got no complaint if I
              ifconfig with the interface up and the lladdr was indeed changed.
              However the interface stoped receiving anything unless I
              change the lladdr back to the hardware value.  So it didn't work.
        \_ Someone here says the ifconfig commands don't actually change what
           MAC address is used; you need to recompile the kernel to enable it.