Seven years to the day of his imprisonment he received, as a sort of mockery, a 500-sheet spiral notebook and a pen. For over six and a half years he requested, in increasing desperation, for a notebook and a pen to write and ponder his thoughts in. His ideas were his most precious companions, yet they left him soon after arriving, causing miserable heartache and unquenchable frustration. He opened the notebook, brought up his new Bic, and hesitated. Holding his breath, he sized the invaluable white page. Slowly, he brought his pen down to touch the left uppermost corner of the sheet. He wrote his letters very small and tight, so that they all might fit. Five hundred sheets to last five hundred more years. He felt excitement under his dirty rags as he wrote his first words: “Today I will live forever.”
That’s actually pretty cool … I like that. 
Marquis de Sade, Dr Martin Luther King Jr, Henry David Thoreau. Didn’t all of these guys write from jail?