If you have a Texas Instruments WiLink 8 (and probably 6) and you get a weird MAC address like:
wlan0 Link encap:Ethernet HWaddr de:ad:be:ef:00:00
This is likely because the default TI distribution of firmware distributes a file called 'wl1271-nvs.bin' in
/lib/firmware/ti-connectivity that overrides the built-in MAC address with this silly address.
To fix, simply:
rm -rf /lib/firmware/ti-connectivity/wl1271-nvs.bin