Can a WIFI mac address be hacked

I currently have a linksys wifi 802.11b access point setup in my home. I have all the security features setup, but was curious if it is possible for a mac address to be hacked or duplicated. I obviously have mac address filtering setup. Also, is mac address filtering an almost guarantee to keep unwanted users from gaining access to my network.

Spoofing a MAC address is pretty easy actually. Plenty of wireless sniffing software that will give you that kind of information for active WLAN's in your coverage area. Still a good idea to enable MAC filtering but if you get someone who really wants in, MAC filtering is little more than a speedbump. WEP, or WPA if your hardware supports it, MAC addy filtering, ACL's if your device supports that and lock any shares down with permissions if you have shares up. You do all that and your pretty safe. If you have sensitive data or are a business then having a VPN tunnel or some form of radius authentication is essential in a wireless LAN or WAN environment.

Many cards make it easier than a reg hack. It's a simple gui change in the drivers properties itself, directly from the network properties in the control panel.