Import your (DRM-free) epubs and PDFs into Google Books

I can't believe I just found out about this, but Google has added upload functionality for your books to Google Play.

To upload a book on the web, just go to Google Play -> Books -> My Books (or go to https://play.google.com/books/uploads )...

 

Then, on the right side of the screen, click the "Upload files" button.

An upload dialog will appear.

Select the files you want to upload, and they will be immediately uploaded and imported! (Google notes that large files may take some time to be processed.)