CFC vs. CFINCLUDE for function libraries

Can anyone please briefly discuss pros and cons of using a CFC as opposed to a CFINCLUDE for function libraries (collections of common functions used throughout an application)?

It depends on what you want to do. But CFCs support more OO elements like encapsulation, polymorphism, and inheritance. If all you need is a simple set of UDFs, an include might be fine. But even for simple sets of UDFs, nowadays I create a Utility (or whatever) CFC, instantiate it at request start (or into the application scope at application initialization) and then call methods on it. That way you can pass the Utility CFC into your other CFCs in the future while maintaining encapsulation.

I have other low-level programmers mucking in my code, so if I don't want them to touch something or break something I put what I can in a cfc. They don't go in those files so it's more safe than in an include. Just a learned preference.

Encapsulation in action.