This  I think is the coolest thing ever:

An occupational therapist and clinical researcher Stephens built the leg after someone jokingly told her to do it!

“Challenge accepted. I liked the idea, because I am very comfortable with my body and like encouraging others to be more comfortable with theirs.”

It’s kind of like the man (I think he was in China ) who built himself an arm (with working fingers) out of scrap medal,but he could only wear it for short periods of time because it was so heavy.
Check out the video