I launched @USPrisons on Twitter a few weeks ago. It will output every prison in the United States – or at least, I think it's all of them. I found a website with the data, did a bunch of parsing and cleanup, and ended up with 4763 prisons. The bot should spend a year listing them all, along with a few stats, and a picture if possible.
If you're interested, I released the code that does the parsing on github.