I've just posted a fairly in depth Cat tutorial, and the Cat version 0.9.4 ... it's been a long day.
I've posted a new Cat tutorial, which provides a (hopefully) half-decent introduction to programming in stack-oriented and functional languages.
I've also posted a new Cat version 0.9.4 some bug fixes, new tests, and more commands.
The "manual" page is still quite rough around the edges, and I plan on fixing that up soon.
On the horizon is a detailed explanation of the inner-workings of the interpreter, and type-inference engine.