Colour-coded battery charge level and status in your bash prompt

I recently purchased a laptop, and having installed a proper OS,
I found myself a little disappointed
with the default battery meter provided by GNOME.
Unless you mouse over the icon on the panel, it doesn’t display
exactly what charge level it is at. I am aware of the other options
such as conky, gkrellm, screenlets, etc, but being the lazy sort, I
consider it a long way to move your eyes! Since I’m the type who always
has several terminals open, I thought it would be handy to display the
charge level and status of the laptop battery in my shell prompt.