I still don't like the idea that given the importance of the test to a student's career, the time required to prepare for it, and the ordeal of traveling to a testing center (which can be far away depending where you live), that walk-ins run the risk of being turned away at the door on test day. Even though walk-ins are usually taken from what I heard, I'm sure it varies by subject and by testing center. I wish ETS had a more organized, less last-minute way of dealing with unregistered test takers. If they made it that registered takers had to confirm (online) the day before the test that they were actually coming, and then post online how many extra test takers they could accomodate at each center for each test, and then offer these seats online, it would be much more fair.
I planned ahead by registering for both the October and November test the year I took it, knowing that I would not get my October score early enough to register for the Nov test if needed and I wanted to get my preferred test center. In fact we didn't even get the score until the day of the Nov test. So those of us who took the Oct one had to decide based on how we "thought" we did whether to attend the November one. I figured I did well enough so I canceled the Nov test after the Oct test and got half my money back. So it cost me like 60 bux but the peace of mind was worth it.
Heh, I guess it never occurred to me that people would be taking other subject tests at the same time!
Well what surprised me was that we all took the tests in the same room.
My test would say, "Consider a nonrelativistic electron..."
And the girl's test next to me would say, "Consider a retarded schizophrenic pyromaniac..."
As for the guy who asked whether there are breaks during the test, it should be pretty clear after reading the ETS website and prep packet they sent that there isn't one.
3 hours is (I surmise) chosen carefully... it's essentially the longest test you can give without needing to break it up into parts. That way they can test as much material as possible without the logistical hassle of breaking it up into separate sessions, which would increase the cost, torture level, ease of cheating etc...
Just plan ahead and make sure you will not have to go to the bathroom during the test. Eat the bare minimum so that you can function but you won't feel the urge to go during the test. You won't even notice if you're hungry during the test, but you'd certainly feel uncomfortable if you have to go. I think all I had that morning was milk.
As for the day before, try to relax. It's not the time to cram more physics in. Hopefully you've been keeping a notebook with random notes and a list of equations. Just focus on that stuff the day before.