Perhaps the most exhilarating experience that you can have while remaining fully clothed is one of the famous jet boat rides along a river. You can do two different ones close to Queenstown. The Dart River Jet Safari takes a full day, and goes the full length of the river at speed, while still giving you the chance to take in the beautiful scenic countryside.
If that's not enough for you, then try the much shorter, much faster, and much more terrifying Shotover Jet, where you can bounce along the Shotover River at what seems like colossal speed through narrow canyons, and over big rapids for around an hour and a half.
