Try reading digital books in a virtual world published by a real-world publisher. Penguin is planning to introduce digital books to the online world of Second Life, starting with the aptly chosen Snowcrash by Neal Stephenson.
What is Second Life? Ah, let me quote Jeremy Ettinghausen, Penguin's digital publisher:
For those who don't know, Second Life is a virtual world (a 3D MMOG in geekspeak), where the residents themselves create and build the world which includes homes, vehicles, nightclubs, stores, landscapes, clothing, and games. People also design their representation in Second Life, which can be pretty realistic, or totally outlandish (I met a Penguin author in Second Life whose avatar is a hippo!). In some ways, it's a cross between myspace and collaborative virtual lego, though some see it as a possible future of the internet.