Just wanted to share a recent experience with my Mac when I was down in La Manz last week.

Shortly after I arrived, my Mac computer started acting "on the fritz"--screen moving left to right, jiggling.
-curser and track pad not working.

Got on the phone with Apple support and worked with a private tech guy in the states and between the two figured out that the trackpad was "shot" (my computer is almost 5 years old), so I thought it was time to get a new computer.

A temp fix--using an external mouse--fixed the problem.

BUT:
A day after I returned to Boulder, CO, where the humidity is in the single digits my trackpad was working fine!!!

So, lesson here is that if your computer starts to act up, consider getting a dehumidifier, or keeping it in a room with AC where the humidity is lower.