Doesn't Everyone Hold Their Breath In Class?!?!?!?

So, in my last Wednesday night marathon of the year (it's a three hour class, and one of the driest I've ever taken), I was bored, as usual. So bored in fact, that normally interesting things didn't even seem interesting. Normally I can get lost thinking about stocks, the economy, trying to come up with a new way to evade taxes, or simply thinking of how wonderful life will be starting in just...and counting down the seconds till the end of class. This night, however, boredom was more stark than usual, so, I resorted to my normal resortation, holding my breath. I probably hold my breath in about 1/3 of my classes, with nothing else to do I just figure I might as well try and expand my lung capacity. Normally I can keep it under control, and not have a huge breath afterwards, but tonight I slipped up. I was counting...1 minute...1 minute 5...1 minute 15...1 minute 25...and then comes a girl, decently attractive, into the classroom. She was about 30 minutes late, and she happened to sit right next to me on my left side. Right as she was sitting down, I hit my target, 1 minute 30 seconds. BREATHE I DID, not dramatic in sound, but not subtle enough to stay under the radar. The two gentlemen in front of me chuckled, as they knew what I was doing, but the girl next to me must have thought it was something she did, for she gave me a look of worry/confusion. She must have been trying not to alert the teacher to her late arrival. I didn't stop my breath-holding exercise there either, and I was careful to not make any sound from there on out, but I couldn't help but squirm a little bit in my chair, and I think she noticed. As I had no where else to look whilst holding my breath, I simply looked in the direction of this girl to see if she was going to catch me holding my breath again, I was going to see if I could do it without being caught. My guess is she never figured out what I was doing, and I hope it to be that way, but...clearly, she didn't belong to the club of those who hold their breath in class, else she would have known my secret.

So, Family poll...How many people held your breath in class to pass the time?