I've been working on a PureBasic port of GNU Rocket and I think it's finally usable so I made a git repo (my first one!) to host it: https://github.com/Dartcode/pbrocket
In case you don't know what the original Rocket is, it's a tool to help you synchronize your demo effects/scenes with the audio. It comes as a C file you include in your demo, and a tracker-like editor used to input your variables values.
The examples (one with native audio and one with BASS lib) should get you going, and I hope you'll find a use for it (it can be used for demos of course, but also for slideshows, subtitles and whatnot)
I also included a remake of the original sync editor which, while it misses select/copy-paste features, should be compilable on OS X and linux. I think you'll need to change the font for one available on your system (any font should do, as long as it's fixed-width)
Hope you'll have fun with it

Lush