Neck problems, mental health problems (stress / burnout). Not convinced about long-term eye problems though (no good science backing that up) http://www.medbroadcast.com/channel/eye-health/caring-for-your-eyes/do-computers-cause-eye-damage
Awesome answers by HAPPY TO HELP. Mouse mat with gel support for wrist. Regular breaks (to reduce physical and mental stresses). Put Base of monitor at eye height, as this naturally encourages you to have better posture. Standing desks also good. Mental health is too complex to go into! But take your holidays, work hard / play hard / rest hard.
