3Aug/110
Zorbing
My wife and I went to New Zealand back in 2004 and loved it. LOVED IT! I was looking through some old photos and stumbled across this one:
Becky and me Zorbing in Rotorua, NZ
Ah... good times! It makes me want to go again. I just checked out http://www.zorb.com/zorb/locations/ and found that they have a location in the US! We'll need to plan a trip to Tennessee soon. 
If you aren't familiar with Zorbing, the basic idea is that you climb inside a gigantic plastic ball and then roll down a hill. It is a blast.