things I learned from DEAD HEAT... (mild spoilers)
1) Being brain-dead for a certain length of time makes one "completely obedient"
2) Zombies only "die" after either being electrocuted, exploded, crushed, or an unspecified number of bullet hits.
3) Zombies still bleed from gunshot wounds, but not from cutting their arteries on glass.
4) Zombies really, really like Playboy centerfolds.
5) There is no way to open an asphyxiation chamber from the inside... and for some reason the glass is bulletproof, meaning one shouldn't even bother trying to shoot through it.
6) Disneyland has asphyxiation chambers.
7) The dead guy hanging in the fish tank was Piscopo? Really?
8) Security guards are usually zombies and/or armed with Uzi Submachineguns and very eager to use them.
9) Closed-circuit security systems in office building have cameras which actually follow and properly frame the action... and have audio too!
10) Vincent Price is immortal.
11) Joe Piscopo unfortunately is as well.
Others? There's plenty I'm sure.