It's kind of too bad there isn't an option to install it on multiple computers for local LAN play only, even if you don't own the other PC. I'd think for LAN party games this would really make Sins popular and increase sales, but SD would need to figure out a way to prohibit single and on-line play via IC while still allowing the LAN games. In other games that allow this option, usually it prohibits playing multiplayer outside of a LAN and also the single player mode campaign mode, which seems like a reasonable compromise.