LeechBlock: short term +2, long term +0 I tried this for about six months. It helped for most of that time. Toward the end, I just ended up using another browser.

I hacked up my apt-get to ignore requests for browsers and apt-related packages/sources, and I deleted both aptitude and synaptic, and I blocked ways to search for browsers and apt-related packages in my browser. I use ProCon protected by password (a random number which I've pasted without seeing it). It lets me block urls and keywords. It helps.

Getting enough sleep: +2 I learned years ago that sleep is necessary for willpower. It's not sufficient for productivity, but if I'm tired, it's very easy to give in to distraction.

I use "failing to fall asleep" as a motivator to do useful work. It's "okay, feel free to, consistently, either sleep or work".