Very nice! Note if you put the | at the end of the line the whole command is copy and pasteable.

Also you could pipe to `column -t -s:` to align nicely

Also you can download the 57K index rather than the 1.3M manual to get the command list.

    curl -s http://www.gnu.org/software/coreutils/manual/html_node/index.html |
    sed '/<li>.*-inv.*p>:.*[^>]<.a>/!d;s/.*#//;s/-inv.*:/:/;s/<.a>//' |
    sort |
    column -t -s: