Also known as Zorbing. An activity that has found it's way across here from New Zealand, we had been planning to do this since Gordon and I bought it for Dad as a Christmas present in 2003. However, last summers bad weather, coupled by a number of problems with the ball meant that is wasn't until now that we could do it.
It's a strange experience. The hole to get into the ball is a little on the neat side. You are encouraged to run and dive in, which produced some amusing results, but it does give you a bit of momentum to get through. You then strap yourself in a full body harness, and are then pushed off down the hill.
Each roll must only last 30 seconds or so, but by the time you get to the bottom, it's enough. On my second run, the ball stopped with Katie and myself suspended upside down, and we had to wait until someone came and pushed the ball over!