hmmm... well the best answer would be a box containing the title deed to the prison and a fuck ton of cash. with my legal ownership of said correctional facility and infinite funds, I start by moving the other inmates to another facility, and renovating my prison, so that instead of consisting of a block of caged cells, its interior now closely resembles that of a palace, with swimming pools, lavish furniture, movie screen sized TVs, butlers, and other such luxury's. I then proceed to live out the remainder of my life sentence in absolute opulence.
alternatively, the Title of Head of State of whatever country I'm in. once I have this, I pass a law requiring all prisons must resemble the one described above.
ore, a machine gun armed fembot sex droid, like the ones in Austin Powers. for absolute protection and for company.