How about a simple C or Perl routine that can get and set the affinity for any pid? By name? by Tid? By user?...
I can think of a few uses for cmd line control -- like setting all my "background" system processes to run on cpu-0, all of my direct-service system or background (mouse control, security monitor, DNS, etc) processes (ones that clients have to wait on for services) on 0-or-1, Then isolate a game on 2 & 3. Since 2+3 share a cache on Intel -- with an 8MB cache, and 2+3 dedicated to game -- no matter what thread is running on which processor, more chance of sharing cached code.