What do you mean by proper here? A proper noun (
http://www.usingenglish.com/glossary/proper-noun.html ) is the name of something and an abstract noun (
http://www.usingenglish.com/glossary/abstract-noun.html ) refers to something that has no physical existence.
If you mean abstract nouns, you could say music, peace, happiness, love,pain,etc. If you want words that are both abtract and proper nouns, then maybe you could have Hell and Heaven, though I'm not sure if religious people would agree.
