Now you can download old books from Googles in PDF format.
But here is the best part,check the following picture:
Google has scanned every single page, including the empty ones of old books, then they have inserted these images in PDF files. The result are huge files where is impossible to do a search for a word or sentence; you can't look in a PDF for a word that's part of an image. They should have converted each scanned image into text and then create with that text much smaller PDF files with full search capability.
What a waste of HDD space and resources!