Though I can't keep up the 1-a-day schedule we normally have when three people are posting, I do think that I'd like to take advantage of the fact that I have total control over TDY for the next few days to do a few more simple yoji's that are in fairly common use and would be good for you to know. Do remember, though, that I'm really just doing these as they come to mind and not really in any particular order, so you shouldn't consider any one necessarily more important that the other.
Let's start off with the characters themselves:
危 is one you may know, meaning dangerous (あぶない is the most common reading, though there is also my personal favorite, あやうい). 機, which you might remember from 機会, or the ever-forthcoming 機嫌, is a little harder to translate, but you might think of it as a chance or a situation. A dangerous situation, therefore, is a 危機, or a crisis. In fact, you can link this word to the last yoji to form 絶体絶命の危機! 一髪 combines 一, which is "one," and 髪, which you might recognize from 髪の毛, or hair (from the top of your head). "One hair" here is used to emphasize the tightness of the situation - the width of a single hair. Which brings us to our:
1. Between a rock and a hard place
2. A critical, delicate situation
3. Close call
It's five minutes to deadline! If TDY isn't updated, it's finished! I, the great Nirav, shall save it in its moment of peril!
All joking aside, the Bruce Lee film known alternatively as "Fists of Fury" and "The Big Boss" in the US was titled in Japan as, ドラゴン、危機一髪！ Quite possibly my favorite yo-ji in a movie title EVAR!