Identifying a MAC

[#1]

I'm trying to improve the setup of the wireless network at home. Between my wife, my sons and myself, we have 5 pcs on this network.  This gives me 5 IP Addresses each with a MAC Address.
So that I can identify on the list of equipments attached to network which pc is which, please would someone answer the following:-
If I am working on a pc how can I identify its MAC Address?
Thanks in advance

[#2]

Have a read of this
http://www.wikihow.com/Find-the-MAC-Address-of-Your-Computer
When I set my wireless network up I looked at the attached devices in the router (dg834g) interface and figured out which was which by turning them off one at a time. When I knew what was what and set up the access list I gave each one its own name.
Simple and worked for me!

[#3]

From a cmd prompt ie start run/cmd type ipconfig /all and look for the line
Physical Address. . . . . . . . . : 00-19-66-39-5D-Ca this is the mac address

[#4]

Thanks fellas. Have identified all the MACs and which PC they refer to. Have edited the list of pcs allowed on my network and given each an identifying name, but for one pc, the name that then comes up on the list of connected pcs hasn't changed from its old ID. I haven't forgotten the Apply button. I didn't use it until I had edited all of the pc names, so the new name should have come up with the others - they did, it didn't.
Oh the mysterys of life.
Regards and thanks

[#5]

At least you know which computer has no name  

[#6]

Arnt we sad when we have to name our computers its like having kids