Yup, but wouldn't advise it. Decided last August I wanted to take the September 7 MCAT but the only slot within 4 hours of me was, well, 4 hours away in Asheville, NC (from around Columbia, SC). I drove up the night before, got royally lost despite my husband's GPS in the Prius (those things are designed for people to pay attention to, not to try to override with mundane things like Yahoo directions) and couldn't sleep in the hotel bed. Awoke overtired and was a few minutes late for my test when I couldn't find the place again (actually scoped it out the night before but it looked different in the daylight) and was chastised by the Prometric employee that I should have been half an hour early. Pffftt.
Showed up on time yesterday--just on time--to my local Columbia, SC appointment and had to wait 25 minutes to be checked in. Didn't finish the exam til after 715pm. Still, it was nicer not to have to drive too far home after that.