*'''Spending too much time in front of computer''': Computers are lovely, nothing helps as much as they do. But if one spends 8-12 hours a day in front of lovely computer forwriting letters, ICQing, and anything which can be transmitted in a spoken formit may seriously destory his/her human habits.*3D-modeling(unless at the job), 3D gaming (insluding my favourite MS TranSim)it can easily causes dizziness, and again destroy human habits and human 3D perception.that's why I wrote [[this research]].