Not sure if you guys are into modding L4D2, but this mod/campaign is one of the best I have ever seen.
It turns all the zombie and character models into minecraft characters, and you can use a wooden hoe to cleave them in two.
Lots of fun, and while it takes awhile to download, the installation is incredibly easy.
http://www.l4dmaps.com/details.php?file=14983Best if played with humans