There is another way to let the machines do the work: interactive evolution. Brian Eno thought of this in 1995 (among others): the system presents you with N candidate patches, you select the ones you like, and it uses your selections to think of N new patches to offer you. Basically it's assisting you in moving forward through the space of patches in search of interesting stuff without having to program them.
Interactive evolution works really well for FM, but systems which provide it are rare. And now for the self-promotion. As it so happens, I just presented a paper on this a few days ago on my system.
EDIT: Great work, adding your paper to my stack of read-todo's...