Set Affinity on a task to tune PC

OK, I just noticed in Windows Task Manager that on a multi-core system you can right click on a task in task manager and at the bottom of the right click menu is "Set Affinity..." Has anyone used that to tune your system ?  I'm thinking that if you set a bunch of the non audio stuff to run on a CPU core other then 0 that would free up power to get the system tuned for lower latency. Does it work ?  I don't have a multi-core system at home yet I just noticed on one of my PCs at work and wondered how well it worked.