Hearing occurs when the ear drum (typanic membrane) resonates to sound waves hitting it. Microphones and the diaphragm in the telephone works in much the same way. Speakers in hi fi's, T.V's etc. use resonance as well.
Resonance is used in guitars and pianos, as well as wood wind instruements.
Resonanse is also used to shatter gall stones in patients using ultra sound. The late Sha of Iraq/Iran had this done.
MRI scans (Magnetic Resonance Imaging scans) are used everyday in hospitals for diagnostic purposes and also for industrial purposes.
A negative effect of resonance could be the effect of waves hitting a rock face. The vibration of kinetic energy from the wave resonantes through the rock face causing cracks and eventually great slabs of the cliff fall into the sea. We have this problem in Swansea.
In a car crash a passanger may be injured because there chest is thrown hard against the seat belt. the vibration can burst blood vessels. Bruising of the skin or internal organs such as concusion of the brain can be casued because of the vibration of a movement.
More gruesomly, I was told by and x army nurse that if your shot with a bullet the resonance of the bullet hitting the body can cause liquifaction of the internal organs, this can also occur if you are near a loud explosion. The vibration of the explosion will apparently burst blood vessels and liquify some of the organs. I suppose the liver and brain, which are jelly like anyway would be easily liquified with an intense vibration.