online-tech-tips.com post a very useful tip on how to change your mac-address. Yes, I too taught it not possile to change a pc’s mac address. Definitely a useful trick.

Step 1: Click on  Start, then  Control Panel, then  Network Connections, and right-click on the network connection you want to change the MAC address for and selectProperties. It will normally either be  Local Area Connection  or  Wireless Network Connection.

If you are using Windows Vista, you have to go to  Control Panel,  then  Network and Internet,  then  Network and Sharing Center,  and then  Manage Network Connections.

Step 2: On the  General  tab, click the  Configure  button

Step 3: Now click on the Advanced tab and click on the “Locally Administered Address” property or the “Network Address” property.

By default, the “Not Present” value is selected. Go ahead and click on the  Valueradio button and enter in a new MAC address. The MAC address is a combination of 6 pairs of numbers and characters, i.e. 40-A2-D9-82-9F-F2. You should enter the MAC address without the dashes.

You can check that the MAC address has been changed by going to the command prompt and typing in  IPCONFIG /ALL. Go ahead and restart the computer in order for the changes to take effect.