Speedometer

[Wrench]

The first green living off the grid, before solar, it was water, wind and pedal operated generators

 

[Squiddley]

I'm not a gym guy by any stretch but I have always wondered why don't they hook those spin bikes up to alternators.
That would become new bragging rights. "I generated 10 kws today, I'm a bucket of chicken.

Darn I may have just given away the next multi million dollar idea.

I saw that on Gilligans Island.