I have since about version 3 or so written "enhancements" instead of hacks. Files that went alongside Threads, but did not change the code "too" much.
This has been MUCH easier to accomplish since templates were introduced, as I typically have all extraneous pages simply linked in my templates, and since they are rarely written over, it makes it easier on upgrades.
My Calendar hack is the only one I am dreading for this next release. The long-time calendar hack is very different than the soon-to-be-released Calendar hack, and I have become very comfortable with the hacked version.
