I've read the whole thing at one point in time. I was an embedded programmer for years, and the availability of bash, and the lack of python/ruby/whatever made it pretty much a necessity.

Once you grok it, it is a pretty excellent tool for testing, monitoring, coordinated pieces, etc. Besides Solaris, I can typically sit down at any type of machine or embedded device and write a fairly non-trivial script without having to ask, "what version of python is installed?" or "is it hooked up to the outside world, so I can install these libraries?".

There's power in availability and commonality even if you give up some readability.