rolf wrotePorn, games, smoking, even some drugs, I doubt these are real problems unless they affect your life very badly.
For example I do not believe that someone has a porn addiction problem if he watches that suff, unless maybe if he misses work because he can't stop masturbating all the time, for example. I guess it's not a clear line. Maybe you can be addicted to anything.
I'm pretty tolerant in lenient in my definition of addiction. Sometimes I think there is no such thing :) or sometimes I think, aren't we all addicted to, say food, for example?
Where does one thing stop being a pleasurable experience, or something necessary, and starts to become something unnatural, destructive and harmful?
A good way to measure addiction is whether or not you get withdrawal symptoms from avoiding the substance. Starving if you avoid food is not the same as having nervous fits if you decide to quit porn or video games.