how2 : stackoverflow from the terminal.
how2 finds the simplest way to do something in a unix shell. It's like man, but you can query it in natural language.
docopt : Command-line interface description language
tmpmail : tmpmail is a command line utility written in POSIX sh that allows you to create a temporary email address and receive emails to the temporary email ad...
howdoi : Instant coding answers via the command line.