Just about anything that one has experience at can be turned into a consulting business. I never heard of a prison consultant until I read a New York Times article titled Making Crime Pay.
If you are heading to prison for the first time and are looking for advice on how to survive such an ordeal, you can actually hire a prison consultant to assist you. With names like Jail Time Consulting, Executive Prison Consultants and the Prison Coach, you have quite a few options. There is even a National Registry of Prison Consultants.
Well entrepreneurs certainly know how to recognize customer needs and provide a product to fill such needs. With public corruption cases existing every where, there is probably a consultant targeting the politician prison market.
If you have come across other interesting consulting fields or services, please share them.