You could write a small program in 68k Assembler to do such a task, but I don't think you'd be wanting to do it via a script, unless you intend to only run the script once at startup.
Also you might have problems launching various ScreenBlanker progs at the same time, as the way they work they tend to set up interrupts which may then clash.
Best idea would be to create a small script or program to launch each time you boot/re-boot to randomly select which screen blanker to run, if that's what you really want to do...
