I was an extra in a very good low-budget zombie film (Dance of the Dead) shot near my hometown (my avatar here is captured from a still). No one was semi-clad but I didn't have to dig any graves either. As with any shoot, there was a lot of sitting and waiting. From the experience, I learned that being a zombie (not just an extra in a movie) was actually boring: look for victims, eat a limb or two, look for more victims, etc. This inspired me to write a script in which the zombies were as normal as everyone else, just undead. There were a few films shortly afterwards with romantic zombies, humanized zombies, etc. I never honed my script to be saleable.