Inmates at the Santa Rita do Sapucai prison in Brazil are being offered a deal too good to pass up-put in 16 hours on a bicycle and get a day knocked off your sentence.
It's an interesting way to encourage prisoners to cooperate and literally work towards their freedom, and the stationary bikes are being used to charge batteries which are then taken into the city and used to power streetlights.
Sounds like a great way to stay in shape, give back to society and whittle your sentence down while biking.
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