Useful for privacy and time-capped WiFi connection at airports.
$ ifconfig -a wlan0 | grep HWaddr
wlan0 Link encap:Ethernet HWaddr 00:16:2B:8D:A2:6C
$ sudo ifconfig wlan0 down
$ sudo ifconfig wlan0 hw ether 00:16:2B:8D:A2:7C
$ sudo ifconfig wlan0 up
$ ifconfig -a wlan0 | grep HWaddr
wlan0 Link encap:Ethernet HWaddr 00:16:2B:8D:A2:7C
I think newer versions of NetworkManager get this right. Haven't tried MacChanger.