glider1
Deity
I also leave Civ5 running 24/7 but warning to anyone who owns expensive hardware, be aware that Civ5 can actually use a lot of resources in the background and shorten the life of your hardware EVEN if it is in the background. Check whether it is with CPU and GPU monitors. I personally force Civ not to use any CPU/GPU in the background with special apps. Also if it is on permanently and you are are running AERO in Windows 7, you need to restart the desktop manager service periodically or else Civ starts to use more GPU than is needed over time. It can make the difference between 70% GPU and 99% GPU depending on hardware.