[persephonevii]

Is there any software out there that can cut off certain programs, or block the internet for a set amount of time? I often get distracted by the net and end up procrastinating. Cutting them off after a certain time or blocking them altogether is something I'd love to be able to enact on my own software (particularly the web browser and the Internet connection). I have heard it can be done, but I don't have any names? Anyone got any suggestions?