just look at the size of this dudes tires, they are like beach balloons!!
i bet he can even ride on sand with them and have no problems.

http://www.youtube.com/watch?v=wphJoasgZgc&feature=g-u-u  喜歡(2)+ 展開- 隱藏

I have tried riding this fat tire bike before, It's just like a mountain bike, the tires are not heavy, but the price is quite high.