Yes, MAC addresses can be spoofed, but that can have unexpected effects on your local network depending on circumstances - If anyone changes a MAC on my local net here at home they'll be denied access to the entire network; the same applies in my office (BTW, I can't really understand why anyone would need to change a MAC address for TeamSpeak, but that's OT).
In the TCP protocol, a "valid" IP address is essential to keeping a connection running - you can't just modify the source IP address on your outgoing packets, since any responses would be sent to the machine that really holds that IP address. For most people, the IP address that presents on the internet is allocated by your ISP and you can't change that. However there are anonymizing services (like the Tor network) that can act as proxies so an individual's IP address is hidden. These are often used by spammers, so they're now well known and frequently the entire range of endpoint IPs presented by these services are blacklisted and blocked.
There are many features that could be used to build an identity of the client PC, but you'd have to make sure not to use anything that is Windows specific. A lot of PCs, particularly laptops, now contain an "asset tracking ID" to combat theft and to allow corporate owners to ensure that all their PCs are updated regularly, etc. I also think (but would need to check) that most reasonably modern processors contain serial numbers. It could be possible to construct an ID using a combination of these features.
I still think a hardware based ID is preferable to a mandatory fee. Cyan have never directly charged for any incarnation of Uru (e.g. during GameTap MOUL, subscriptions were paid to GameTap not Cyan) so they do not have the software that can correlate fees/donations to specific user accounts - that's why the donation page asks for an avatar name, as they've no other way of knowing who the donation is from. That would need to be put in place first, so there's an upfront investment before you could start to collect any fees. At the moment, I can live quite comfortably with MOUL and it's little security holes, because it's "just a game". As soon as you start linking credit card payments, etc., to it, then I'm going to become very uncomfortable.
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Mac - MOULagain KI#00004826
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