this may come as a shock to some, but really rare things are often worth money.
Blues records article in Sunday NY Times
In tomorrows NY Times Art and Leisure section their is a great article on a collector of 78rpm shellacs and the status of these rare records. Some of these 78's have sold for over $30k each in the past year. He talks in depth of the roots race blues that were recorded by Paramount Records in Wisconsin in the 20's and 30's. Fascinating article. Being a lover of Mississippi Delta Blues I gobled this up.