If not you, who else?

As the mighty alien fleet from the latest computer game thunders across the screen, Johnny prepares to blow them into the usual million pieces And they send him a message: We surrender.

They're not supposed to do that!
They're supposed to die. And computer joysticks don't have 'Don't Fire' Buttons...

Shortlisted for the Guardian Children's Fiction Award

'An impressively original book with its thrills and spills, its inventiveness, its wit and continuous readability' Daily Telegraph

From the author of the phenomenally successful Discworld® series and the Amazing Maurice and His Educated Rodents, which won the 2001 Carnegie Medal.

 
I think this is the first of Pratchett's Johnny Maxwell books, and if that's so I should be reading this in the not too distant future. It's strange to me that I've not read them sooner, especially as I remember seeing them in the library when I was younger...still, there's time to remedy that mistake.