Via Interaction Design Umeå, Freedom:
Freedom is an application that disables networking on an Apple computer for up to eight hours at a time. Freedom will free you from the distractions of the internet, allowing you time to code, write, or create. At the end of your selected offline period, Freedom re-enables your network, restoring everything as normal.
This reminds me a bit of Write Room, and why I like it: it's designed to be distraction-free.
At what point did the absence of distraction become a luxury? Is it just me, or is concentration (not just attention, but the ability to really focus seriously for long periods of time) an ever-scarcer state of being? (I hate to call it a commodity, despite its economic or productive value.)