Originally posted here by HTRegz

WebCarnage: That would be for malicious purposes... I don't see those as "valid" reasons to change your MAC because I don't consider malicious activity to be "valid activity" however yes... that's an example of where someone would change their MAC Address... and I wasn't saying the computer wouldn't be able to communicate if you changed the MAC Address... due to limitations on my LAN at home I regularly set my MAC Address on various machines... What i was saying was that if you COULD mask your MAC.. you would effectively kill communication between your machine and others on the segment.
I'm sorry, but I care very little about what you consider "valid activity."