This script runs cudaminer only if the main display :0 is off. Uses polling every ~10 seconds.

cudaminer-reset

#!/bin/sh
export DISPLAY=:0

while true; do
    # check to see if cudaminer is still alive, (possibly stopped)
    if pgrep cudaminer; then
        #if the monitor is on
        if xset -q | grep -q 'Monitor is On'; then
            pkill -STP cudaminer
        else
            pkill -CONT cudaminer
        fi
    else
        nohup cudaminer # user-specific arguments
    fi
    # poll every 10 seconds
    sleep 10
done