Games developers are really just big kids deep down, and with Halloween fast approaching, it seems they just can't help themselves but to have a bit of zombie-related fun.

First, players of GTA IV reported a zombie "infection" in the game last week. Zombies have been in GTA IV for a while, sort of as a trophy for those who'd completed the game, but this was different.

Anyone killing a zombie during a multi-player game was automatically turned into a zombie (wearing yellow Rockstar Y-Fronts nonetheless) themselves. The catch? Not all zombies look like they have the infection, so you can never be quite sure who or what you're killing.

Rockstar says the sign of infection are "access to the zombie skin and having the acheivement "Let Sleeping Rockstars Lie", and you can now head over to Rockstar's Social Club to check out the total number of global infections and see how it is spreading over the world. We like it.

Elsewhere, zombies have also been spotted in World of Warcraft, it seems as a teaser for the Wrath of the Lich King expansion.

Glowing crates that have appeared in Azeroth’s ports have turned players into zombies. There's a special powers bar unless you manage to get healed within ten minutes of contracting the disease.

Apparently Call of Duty: World at War is set to feature a zombie mode too, playable once you have completed the main single-player game. Four players will work together to fight off the Nazi, and the more you kill, the more money you’ll get to buy weapons and barricades.

Well you certainly can't beat a bit of the undead to spice up your gameplay.