I was just completely freaked out a few minutes ago. All of a sudden in the middle of editing some XSLT stylesheets I started to get a resonating hum similar to electronic interference in the base of my skull at regular intervals. I was about to call 911 when I realized it only happened when I was near my monitor or television and stopped when I turned them off. I called a friend and she mentioned that she'd heard that this sometimes happened to people with silver fillings in their teeth. Since I'd just got some dental work done about a week and a half ago I guessed this might have been some static electricity buildup. So I brushed my teeth and now I don't have the weird hum in my head while using the computer anymore.

Unfortunately I couldn't find anything on Google about this.