Fundraiser for FOSS Music software Open Octave
The creators of "Open Octave", a project providing a collection of midi orchestration tools are running a fundraiser to add new features:
Ironically, one of the features they want to add is Windows and Mac support. At least for once, it's not the other way around! :D
At the moment, it's GNU/Linux only.
The main software (OpenOctaveMidi) is under the GPLv2 license, while icon sets and a sample library called sonatina are CC-licensed.
Source code on Github: https://github.com/ccherrett/oom
Official website: http://www.openoctave.org/