The Pine email client used to have an integrated spell checker. Then Mike Harris from Redhat started to make it more advanced, and it was decided to extract the spell checking element, and simply call it from pine. What actually ended up happening is making pine-spellcheck into a bash script that calls aspell, with a backup to call ispell for older installs.
The practicality of it is that any machine with pine on it ends up with a spell checker that can be called from the command line to check any text file, like this:
topher$ pine-spellcheck blogpost.txt
It tells you what’s spelled wrong, and lets you change it on the fly and add stuff to your lexicon. It’s super tiny, fast, and easy to use. How can you beat that? Granted, it just calls aspell, but you don’t have to remember any flags.