Theo Schlossnagle's cool. He's been involved with the Spread and Backhand projects for a long time and helped us with mod_backhand back in the day when it was kinda new and we were finding bugs.
I was kinda flattered to read he was writing a book in which he intends to discuss memcached, even if it is just in comparison with similar tools.
I've gotten asked twice now by two different publishes if I had any more article or book ideas, most recently just today. I'd write the type of book Theo's writing, if I hadn't seen Theo's already writing it and is probably much more knowledgable in all of it than I am.
A book would be fun if I had somebody to co-write it with, but it's probably a huge project. I think I should just write some more articles. That memcached one has brought quite a number of people into the memcached mailing list and I'm enjoying a lot of the feedback.