haha yeah right, are u kidding me?
I took the SATs twice.  i didnt study for them or anything but the first time I got a 1360 after staying up super late smoking.  fell asleep after I finished every section
next time I was in bed at 10:30.  woke up, ate breakfast, and got there with plenty of time to spare.  I did worse in every section.
if you are already prepared for a test, then staying up late and studying won't help.  but if you can't handle getting no sleep, hope you enjoy college.  I personally love the fact that if I am not prepared for a 9 AM test and its 9 PM, I have nearly 12 hours to study.  and theres few tests that Ive had that require nearly that much studying.
on that note, better get back to studying.