My latest Harry Potteresque fix while waiting for the next book has actually come from the amusing, equally addictive anime/manga "Mahou Sensei Negima", which is released as "Negima!" for the manga title. Think of a young Harry Potter-like apprentice wizard who has been tasked to teach a classful of slightly older Japanese schoolgirls, all of whom have the hots for teacher. His familiar isn't an owl either, but a lecherous, panty-obsessed ermine. The series is actually quite good, and is an excellent reason to use BitTorrent (or one of the BitTorrent-based clients, such as BitComet) which can be used to download "fansubbed" (fan-subtitled) anime and manga. Panties magically dissolve and cute romantic flirtations ensue. Lucky lad.
For those of you who are prone to scream "PIRACY!!!", it might surprise you to know that most anime fansubs are actually quite ethical, and actually help to build the fanbase and encourage anime sales.