A few weeks ago I started unplugging my internet when I go to bed, so it's off when I wake up. Then I work for 2 or 3 hours before plugging it back in. I use DevDocs.io, which has an offline feature, to look up standard library stuff.
I actually delay going online for as long as possible because I know productivity will drop off a cliff once I reconnect.
This is the most productive I've been in my life, by quite a wide margin.
For offline documentation, I use these in order of preference:
• Info¹ documentation, which I read directly in Emacs. (If you have ever used the terminal-based standalone “info” program, please try to forget all about it. Use Emacs to read Info documentation, and preferably use a graphical Emacs instead of a terminal-based one; Info documentation occasionally has images.)
• Gnome Devhelp².
• Zeal³, using up-to-date documentation dumps provided by Dash⁴.
• RFC archive⁵ dumps provided by the Debian “doc-rfc“ package⁶.
I actually delay going online for as long as possible because I know productivity will drop off a cliff once I reconnect.
This is the most productive I've been in my life, by quite a wide margin.