I took my daughter on a day trip to Magic Mountain, one of the better parks around for roller coasters (it's it still not Cedar Point, IMHO, though if you like inversions, Magic Mountain is the place). We went on Friday because she had a special day off from school, and there was no one at the park. In the first 30 minutes, we rode several of the top coasters all alone. The only problem is that I am more used to getting a bit of a break between rides, waiting in line and such. Anyway, we had a blast.
For those not up on their amusement park trivia, Magic Mountain was "Wallyworld" in the movie Vacation and is home to the first ever looping rollercoaster, the Revolution, which was featured in the movie Rollercoaster. Since that first inversion, coaster designers have gone nuts. The first roller coaster we rode on Friday, called Scream, had seven inversions in one ride. It was also cool because it had no car. When we were in the front, we were just strapped into chairs with nothing around us but the track below our feet - really cool. Picture being the front guys in this photo. Through the day, we probably survived 50 inversions.
Coaster designers have really gotten creative. We rode sitting, standing, and lying on our stomach (what is called a flying roller coaster, you are sort of in the same position as in a hang-glider). We rode on top of the track and hanging from the track. One of the challenges of ride designers is to push the gees, both positive and negative, without making it downright painful. Millennium Force at Sandusky Park is rightly considered perhaps the best roller coaster in the world because it plays with the gees without torturing you (the negative-G hills are great). I thought several of the rides at Magic Mountain went over the line, in particular the Batman hanging coaster and the Tatsu flying coaster, when there were a few turns when I thought my head was going to explode. Overall, we liked Scream the best - smooth, fun, scary without being painful.
Update: I said Millennium Force is the best coaster out there. This one, also at Cedar Point, which I have not ridden, is the most elemental -- No subtlety here (go to the POV gallery on the right and watch the video).