Again, this is not actually part of the series ARIA, but I couldn't think of a better place to put this, so I'm listing it under ARIA.
It contains 4 short stories, "Sora no uta," "mahou no yuubin'ya-san," "Angel Voice," "and "Earth II." You can really tell how certain features in ARIA are based on her older works, as can be seen in some of these stories. I mentioned that Amano-sensei must be a somewhat simplistic optimist in my previous listing. I now must take it back. The short stories in this book are a lot more complex. The last story really hits the mark for me. In fact, I think this stuff is a lot more interesting than ARIA's fluffy reality. I guess another way to see it is that in ARIA, she's focusing on the simple yet wonderful things that are all around us, in order to get the readers to wake up and try to get out of the holes that they've been digging for themselves. Heh, what do you know? I'm starting to think positively!
Also, the third story, "Angel Voice," hits the mark for a seiyuu otaku like me. It's a wonderful light fantasy.
All in all, this is a must buy for all Amano-sensei fans, or for people who want to know more about her and her works.