CommandBox is a tool for Java or CFML (a JVM scripting language) devs that provides npm-style package management, command-based CLI, REPL, and the ability to start any CF engine or Java WAR file with zero installation. CommandBox can publish packages to ForgeBox, run unit tests, scaffold sites, and is extensible via CFML modules. In addition to the standard CLI interface it has it's own interactive shell that features better tab completion, basic bash emulation for Windows users, and allows mashups by allowing the user to create scripts that run CommandBox commands, native OS shell commmands/binaries and CFML functions all at the same time.

At a quick glance, this reminds me of Ruby CLI. The fact that it uses CFML as a basis for the engine is great too. I get the feeling that you could write up an API with this in a day and it would perform well.