Would These Bookcases Work for You?

I'm as enthralled as anyone by clever new storage solutions - but I've seen a few new bookshelves lately that just don't seem very practical.




1. The See-Saw Bookshelf [via Better Living Through Design]




2. Quad [also via Better Living Through Design]




3. The Piola wall bookcase [via Apartment Therapy: Los Angeles, which comments "like Tetris for your bound collection."]

Anyone else have thoughts about these?