What would be the funniest fanfiction you've ever read?

Choosing just one is fairly impossible, so I'll give you my top few funniest fanfics (all Harry Potter). There's not all that much between them since they're funny in different ways.

A Sorting Song to End All Sorting Songs by textualsphinx. This is a filk of "I am the Very Model of a Modern Major General" and is written in the style that Severus Snape would write the Hat's song if the task fell to him. Much madness ensues.

Contemporary Magical Innovations by H. Granger. A documentation of the invention of a particular form of wandless magic. The inventors are Harry Potter and Severus Snape. And they... um... have a very *interesting* working relationship.

Albus Dumbledore's Inbox by Indigo Ziona. What if the Hogwarts staff could email each other...

A Cat's Tale by Brandon League. It's Headquarters, late at night, and Harry Potter's "Monster Book of Monsters" has escaped from his school trunk and has now entered a brawl with Crookshanks.

I have to say, the funniest fanfiction I ever read was funny because it was so ridiculous. A lot of people do some lousy fanfics out there, let me tell you.

The one I spent forever laughing at was about two characters from the Godfather in a relationship. It was so funny because they're BROTHERS, first off, and that one of them kills the other in the series. Also, weren't most children of Italian immigrants back then like really religious? Heh, it was quite amusing.

I assume, also, this is what you mean by fanfictions.

I read a Harry Potter fanfiction called "A Pampered Pureblood". It was kinda messed up, but in a really funny way. It involved Malfoy not being toilet-trained, and Harry was the one who had to change his diapers.

Mine is "The Not-So-Comprehensive Guide to Hermione/Severus Clichés in Fanfiction" by Electryone.

So far, it was "To Do, or Not To Do." It was in The Dark Knight section and it was about Harvey Dent making EVERY single decision with his coin. What to wear, ordering off a fast food menu, etc. Made my day. xD