I think my favourite, purely in terms of length if nothing else (feel free to make your own jokes about that comment), is the following magnum opus of cinema:

Night of the Day of the Dawn of the Son of the Bride of the Return of the Revenge of the Terror of the Attack of the Evil, Mutant, Alien, Flesh Eating, Hellbound, Zombified Living Dead Part 2

A masterpiece.

Here are some more:-

* Gore-Met Zombie Chef From Hell
* Monsters Crash The Pyjama Party
* Children Shouldn't Play With Dead Things
* Bikini Bloodbath Car Wash
* Fertilize The Blaspheming Bombshell!
* Weasels Rip My Flesh
* Monsturd
* I Bought A Vampire Motorcycle
* Poultrygeist: Night Of The Chicken Dead
* Stuff Stephanie In The Incinerator
* Werewolves On Wheels
* Sometimes Aunt Martha Does Dreadful Things
* C.H.U.D: Cannibalistic Humanoid Underground Dwellers
* The Incredibly Strange Creatures Who Stopped Living And Became Mixed-Up Zombies
* Chopper Chicks In Zombietown
* The Long Hair Of Death
* Zombie Ass: Toilet Of The Dead
* Let's Scare Jessica To Death
* The Cars That Ate Paris
* Sorority Babes In The Slimeball Bowl-O-Rama

All, I assure you, works of genius.

This may, in fact, be a lie.

The Don't **** in the Woods has a sequel due out soon.

I am not making those titles up, Jaboody Dubs did riffs on them and everything.

I actually watched this one. There's a possessed shark indeed, but it only appears in two or three scenes. Most of the movie is spent on some killer nun and a vampire blonde.

And the Shark Attack genre has plenty of similar "goldmines"

(Attack of)
the 2 Headed Shark
the 3 Headed Shark
the 5 Headed Shark
the 6 Headed Shark

It stops there, however. No 7 heads for now.

...but I have to vote for Fortune Cookie Prophecies.