There is one caveat - if you're playing a modded game on a VAC-enabled server, you could be banned. If you don't fancy getting your hands dirty you can use the Dead Island Helper to enable and disable mods. Dead Island seems to have been built with modding in mind, so from here it's simply a question of extracting the necessary files to C:\Users\\Documents\DeadIsland\out. To get started, it's a good idea to backup your Dead Island profile and save games - you'll find these in C:\Program Files (x86)\Steam\userdata\\91310\remote\out\profile s\default.pro and C:\Program Files (x86)\Steam\userdata\\91310\remote\out\save\sa v_0.sav.
This simplicity has resulted in mods which do everything from make zombies' heads come off every time you hit them, to changing the game to make it more like Crysis.
Open up its PAK files in WinRAR, then tweak certain settings with notepad to your undead heart's content. This is partly due to it being fairly simple to mod, and partly due to bits of it not working on release.