I've just done an extensive Google search for a program like this... Seems these things are very rear.
Only found a LAN emulator specifically designed for Warcraft 3.
In regards to Anibus' message... I don't see why a game would use more network bandwidth on a LAN than on the Internet... If the necessary data can be sent at a rate of 5-8 KB/s (and it usually can), then I don't see why they would want to overload people's home networks just because they were running a LAN game. Think about it... a 10 MBit HUB wouldn't even be able to support 3 gamers at a time if this were the case (the game requiring 4 mbit). Anyway, I'll be sure to test it next time I play a LAN game and compare it to playing the same game online...
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