I’ve been using Inno Setup to build installers for a variety of projects for 5+ years, for both personal and commercial projects. Inno is very high quality software, extensively debugged and robust. I prefer it to the other install-builders I’ve tried, including NSIS and various commercial packages (some of which are truly awful).
When I saw this discussion on Joel’s discussion boards, I realized that I too had benefited greatly from Inno yet offered nothing in return. So today I sent $200 over, and I encourage anyone else using Inno to support the project also.