What very old/unmaintained software do you still use today, and why?
I still use Font Renamer to manage my font collection. It works great but hasn't received an update since 2008. Even the website looks straight out of the Windows XP era.
I like to post to my WordPress blog from my desktop, so I use Open Live Writer. It's allow me the option to write without being connected to the Internet. I doubt it still in development.