You can see the gaming influence in several of the books. In particular, a big part of Snuff was inspired by the goblin caves in Oblivion (IIRC had had a mod created that made the goblins peaceful, and he also contributed to the Vilja companion mod), and you can see his love of the Thief games in various parts of Night Watch and Making Money.

Earlier in time, Interesting Times has a parody of Lemmings.