If you struggle to keep focusing on what you should get done using a computer connected to the internet a.k.a. storm of distractions, I HIGHLY recommend this super awesome and helpful extension. I'm studying, have to read lots of PDFs everyday and couldn't find a better tool for preventing the dark side of my brain from getting lost into distractions. It kind of speaks with you: "Shouldn't you be studying or doing something else?", haha. Having to scratch distracting sites free makes me think twice: "Is it really worth reading or checking this or that while I'm studying/working?" Playful and heplful at the same time :)