134.5 kg Concrete Bike [video]
This reminds me of my own wacky idea for a line of fitness products: ordinary everyday items that are normal in every way except that they are intentionally designed to be physically challenging to use.<p>For example, doors that require a lot of force to open, keyboards with 1lb resistance springs, remote controls that weigh several kilograms, etc.  Since many people have trouble going to the gym, it would be a way to introduce weight training in a way that was both unobtrusive and unavoidable.<p>Just one of those things that has been bouncing around in my head for years now.  I think riding this bike would definitely qualify as weight training :)