I'm wondering about tools that are powerful and that most system administrators either don't know about or don't use (but should).
For one thing, I like the possibility of finding out about a tool that is good and that I should be using - or at least, trying out. I also find that giving these tools their time in the sun (again) can be a positive, letting others know about the wonderful tools that are out there.
Thus, things like sudo, vi, emacs, dtrace, ps, and top are out. I have some ideas but I just hate to skew the statistics...
I'll just wait and see if anyone mentions my favorites.