I don't believe roller coasters are something Christians should participate in. Even those who enjoy them confess there is a fear factor involved, a "thrill" if you will. God has given us this natural fear sensation for our good, not our amusement. (We certainly don't have any indication in Scripture that Jesus pursued entertainment of any kind.) In addition, the Bible says that God has not given us a spirit of fear and that perfect love casts out all fear. To cultivate fear then, especially for something as frivolous, for the purpose of reveling in fear is spiritually perverted. Given all the suffering in the world, including that endured by our Christian brothers and sisters, riding roller coasters at the very least seems like a poor use of precious time, an obvious violation of Philippians 4:8.