However old it is exactly, I've used this editor for decades and I love it. Most recently, I use the Worksheet feature to execute a series of scripts that do all the file conversion and make the RSS feed entries for my podcasts. It's easier to understand than a Makefile (although I do use Makefiles to build my blog posts) and it's all archived; if I need to regenerate anything I can just scroll back and re-run the commands right from the Worksheet file.

I know the Worksheet concept wasn't invented by Bare Bones - I think they borrowed it from the original MPW (Macintosh Programmer's Workshop), which used to be what the cool kids used to build Mac software before there were competing IDEs. But Bare Bones definitely perfected it.