MAC address spoofing
It is possible (for whatever reasons) to make your network card broadcast a different MAC address. Suppose your network interface is
ethX. Then, to retrieve your MAC address:
$ ifconfig ethX
The thing you want is the 6 byte number in the hexadecimal form, something like this:
Changing the MAC address is easy, shut down the network interface, change the MAC address and restore the interface. This can be done succinctly, as root:
$ /etc/rc.d/network stop $ ifconfig ethX hw ether FF:FF:FF:FF:FF:FF $ /etc/rc.d/network start
FF:FF:FF:FF:FF:FF is your new MAC address.