Limits on addictive behavior

I want to commit to some limits on addictive behavior. So far I have 1) no more than two cups of coffee and two cups of tee per day, 2) no more than 2 x 15 minute gaming breaks.

I have a sort of flow chart to fighting off sleepiness. Caffeine --> exercise/news reading --> email --> web surfing/gaming --> napping. (X --> Y means if X doesn't work, do Y)