It is my understanding that for the 35 bucks to the US Library of Congress, one can submit a "group" of songs. You could, for example, name your submission "The songs of" or "the works of", followed by your name. At any point if a publisher or an artist wants to "use" just ONE of those songs, you can then pay another 35 and get a copywrite for that ONE song that you extracted from the group. I think the deal is that even though the songs are fully protected AS A GROUP you still cannot give permission for someone to "use" one of those songs until it is INDIVIDUALLY copywrited. Personally, I think it is a great way to protect ones songs, and yet not "tie them up" in case someone is ever interested in one of your songs. Hope this is helpful. You should be able to "read up" on all this at the Library of Congress website. You might also want to google "Creative Commons", which is completely free, and look into that as well.