I love that one. It just never gets old, especially since I had a similar interaction with an end user just a few days ago.
As far as ebooks go, I am of two opinions: books that are read linearly or are purely reference material are excellent for ebooks. However, I've never had an easy time with the kinds of books that I just like to flip through (like game books.) I would buy a lot more from DriveThruRPG if I had a better way to read PDFs that are designed for print (portrait and 2 column layouts are horrible for widescreen monitors.) I'm debating about getting a 10" tablet just so that I have a good device for reading all the PDFs I've accumulated.