Running 'Doom' on a Canon printer

I stumbled upon this interesting article about decrypting firmware of Canon Pixma printers.

http://www.contextis.co.uk/resources/blog/hacking-canon-pixma-printers-doomed-encryption/

Pac-Man - level 256

Ever wondered about the infamous level 256 of Pac-Man? Don Hodges has an in-depth explanation of the phenomenon, together with code examples and a patch for fixing it. Read on.