I can't stand it!
It's bad enough when someone accidentally leaves his phone on during shul - or perhaps intentionally, but hoping not to get caught - and gets a call in the middle of shemonah esrei.
It's even worse when some guy's phone goes off, particularly with this annoying as all heck ring:
and the jerk is too absorbed in his kavana to turn the darn thing off.
Seriously, if you were really thinking about davening, you would have made sure to double-check that your cell phone was powered off in the first place! Now, that it's YOUR phone that's ringing, you pretend to be having such hailege concentration, breaking down the gates to shomayaim with your prayers, and distracting the rest of us with anger because you won't silence the stupid thing.
So while you're having a grand ol' time davening away, thinking we might not notice your phone ringing because we're also reaching such heights in our prayers, instead, everyone else in the room is silently cursing your disrespect for the shul/beis medrish, tefillah, and most importantly, G-d Himself.
At least when someone mistakenly forgets to turn the phone off and fumbles to silence an unwanted ring, we feel bad for the guy. Yes, we're a little perturbed, but we appreciate the effort to remove the distraction as soon as humanly possible.
But not you, Mr. Let It Ring Dude. Excuse us mere humans for being distracted by your unexpected and unattended phone ringing in your pocket, because we are but mere flesh and blood. You, on the other hand, must have some sort of spiritual level I've never heard of (over 9,000!?) that lets you completely disengage from your corporeal self while you ascend the 7 realms of the heavens and present your heart-felt requests at the very metaphorical feet of the Ruler of the Universe.
This crime is awful in and of itself, no matter where it happens to take place or what particular prayer service it rears its ugly head. However, allowing this to happen in the main Beis Medrish at YU (aka the Glueck Beis Midrash) while Rav Schachter is davening with us? For shame, man!
Mr. Dude, do some teshuva soon. By the way, this would include (according to the Rambam) not ever letting this happen again. However, we will find it in our hearts to forgive you if you accidentally leave the phone on and silence it immediately after it goes off and then proceed to apologize profusely to the congregation after davening is over as part of your penitence.
Every Other Person In The Shul