I don't know about crowd source, but one of my favorite solutions come from the ElementaryOS team. Their software store allows you to pay for what your download

I don't know about crowd source, but one of my favorite solutions come from the ElementaryOS team. Their software store allows you to pay for what your downloading and I think that goes directly to the project? So its like opening the GNOME software center, but having the ability to donate right there as you go to download it.