The free version of Cold Turkey offers plenty of features, and is easy to use. You can also donate $5 to developer and self-described "student in need" to get a more powerful version that can block executables, such as games, and supports a time frame of up to 30 days (compared to 7 days for the free version). Combined with screen-recording utility , these two programs form a powerful duo of productivity-enhancing tools for changing long-time habits and getting work done faster and with less stress.