SMAC (Software MAC) is a simple GUI utility to list details of your MAC adresses, IPCONCIG information and allow you to change or even spoof MAC Address on the fly. SMAC also has a simple 1-click restart for the network adapters when you need to refresh settings.
I just now wrote a Windows Tweak to manually change the MAC-Address on your NIC from Windows Registy here. If you thought, its too much to ask then here is a simple tool that exactly performs the steps we performed with a few clicks.
Technitium MAC Address Changer allows you to change Media Access Control (MAC) Address of your Network Interface Card (NIC) irrespective to your NIC manufacturer or its driver. It has a very simple user interface and provides ample information regarding each NIC in the machine. Every NIC has a MAC address hard coded in its circuit by the manufacturer. This hard coded MAC address is used by windows drivers to access Ethernet Network (LAN).
MAC-Address is the hardware Network Address for the NIC which is unique for the system. However, there may be time when you need to change the MAC-Address for administrative purpose on a network. Some of the device drivers come with an option to change it from the device properties but not all (like my Broadcom Gigabit Ethernet Driver). For those who do not have the luxury of changing the MAC-Address from the device properties there is a way to do this by editing the Windows Registry.