Digging this thread out for ideas.

DS7 is in love with the Artemis Fowl series. He's 2 books away from the end and I'm wondering what to get for him after this.

He's sensitive, so Harry Potter won't do. He's worried by the cover of the Lightning Thief series so he hasn't taken to it either. I haven't read the Artemis books myself but he says he loves the wicked humour compounded with the high tech, science-y feel of the books.

Any suggestions? Is Septimus Heap and Tamora Pierce in the same vein?