[silentbicycle]

While it's somewhat old, _The Unix Programming Environment_ covers the mindset and a lot of the fundamental tools. _Unix Power Tools_ is another good one. This stuff is particularly novel to people who learned Unix from e.g. Ubuntu + GNOME and worked towards the command line, rather than starting there.

A lot of the tricks listed in the article should be in the man page for sh. I've found a lot reading man pages, but I also use OpenBSD rather than Linux, and its man pages are often noticeably better. (The "we only have a man page to remind you that info is better" pages for GNU utils on Debian are among the worst man pages.) Either way, "apropos" and man pages' SEE ALSO section should help.

I've also found several cool utilities looking at summaries of what was available in the OpenBSD & FreeBSD ports trees, especially in the sysutils and devel categories.

Finally, people who are already using ratpoison/dwm/wmii. as their windowmanager, mpd for playing music, etc. tend to have a common aesthetic, and can usually recommend several other tools. Check out http://onethingwell.org and http://suckless.org for starters.