You might be wowed by the fact that Spring Design's Alex e-reader runs Android, or includes both a 6-inch e-ink display and a 3.5-inch LCD screen. But the best part is that those screens have the ability to work and interact with one another -- kind of like a Nintendo DS.
Imagine reading a news story on the e-ink display that happens to have a video clip associated with it. You could hit a button to play that video on the LCD screen below. Perhaps you want to add a few notes, images or links of your own to a book you're reading. You can tag certain passages with "web grabs." Or maybe you're browsing the web on the LCD screen and you see a story you'd like to read. You can send it up to the e-ink display for a bigger view that also conserves battery life.