I didn't know this "enable -f" feature of bash, it's certainly handy. What are some other interesting binary bash plugins?

I really like this one, most certainly one would use it to build specialized bash libraries that wraps all the ugly stuff. Like a speedy sqlite3 bash library that keeps a database connection open and you can build up transactions by multiple bash commands, it would be a nice alternative to calling sqlite3 multiple times or building a huge sql statement and then calling it once.