There is Lazarus, which is an open source Delphi clone based on Free Pascal. Haven't tried it yet though. But the file manager I use daily (https://github.com/doublecmd/doublecmd) is written in it, and I have some ideas for improving it, so maybe I will try to compile that project for good old time's sake...
For anyone that's curious, popular game hacking/reverse engineering tool Cheat Engine(basically a fully fledged Windows debugger nowadays) is also made in Lazarus - though I can't seem to come up with anything else that is from the top of my head.
