nice bit in the feb 2012 issue on the kindle stuff.
nooks also can do that. not as easy maybe though. youll need Adobe Digtal Editions
software on your PC, a nook device or the free nook readers (available for PC or Andriod). and of course a library card.
now check your local library to see what they offer. in central/western mass, its C/W MARS (Central/Western Massachusetts Automated Resource Sharing), a website with ebooks you can borrow. other locals have similar offerings.
sign up, search and download the ebook to ADE. then sideload to the nook via USB. presto, you have borrowed an ebook. you can load the book to up to 5 nooks.. real nooks or software ones, and it syncs reading between them all. great for reading a bit at lunch on the phone, then resuming where you left off on the e-ink nook at home. be sure to "return" it as soon as youre done for the next person.
Im sure there are many other variations of this.