juneBungie included an extra serial number with every copy of Marathon 2 for Macintosh that only allowed for network play
there would be two keys with every copy bought, a Full key, and a Net key. the person who bought the game would install on their Macintosh, registering with the Full key, giving them full access to the singleplayer, multiplayer, etc. facilities. Then, there was another key, the Net key. This was so you could take your CD and pop it in a friend's Macintosh, install, and instead register with the Net key. This would block off the singleplayer, but would provide a unique key, allowing a friend of yours to play netgames with you; you could technically give them the full key too (it's illegal), but then they wouldn't be able to netplay as it checks keys against eachother.
From the manual: "If you want more than two players in your net games (highly recommended) call us with your credit card number."
there would be two keys with every copy bought, a Full key, and a Net key. the person who bought the game would install on their Macintosh, registering with the Full key, giving them full access to the singleplayer, multiplayer, etc. facilities. Then, there was another key, the Net key. This was so you could take your CD and pop it in a friend's Macintosh, install, and instead register with the Net key. This would block off the singleplayer, but would provide a unique key, allowing a friend of yours to play netgames with you; you could technically give them the full key too (it's illegal), but then they wouldn't be able to netplay as it checks keys against eachother.
From the manual: "If you want more than two players in your net games (highly recommended) call us with your credit card number."
Netzblockierer