[sv]creative]what's been done

Some ideas have been done before. Really. They're over. These are those. If you decide to make a hoax like one of these, make it a completely new take on the situation...

[1]*character* in *earlier game*

You know the kind of hoaxes I mean. Shadow in Sonic 1. Super Sonic in Sonic 1. Amy in Sonic 2. Alright. We get it. Characters can be put into games that were released before that character first appeared. This ESPECIALLY applies to the following zones and characters:
Sonic 1 Green Hill Zone, Final Zone.
Sonic 2/ Sonic 2 Beta Emerald Hill Zone, Hidden Palace Zone.
Sonic 3/ S&K Hidden Palace Zone.
Characters Super Sonic, Amy, Tails, Espio, Knuckles. If you must do a hoax like this, make some kind of interesting twist to the situation. Please.

[2]fart jokes
They're not funny. Really. Someone passing wind is not a joke in itself. Please, please, please, don't do it.

[3]one-panel sprite comics

A one-panel sprite comic is just a plain, out-and-out gag, especially one that involves your own fan characters (but more on that later.) Now, single-panel gags can be really, really cool, but when they fall flat they fall very flat. It's also a single-panel sprite comic if it has no HUD (score/time/rings layout) when it should have one. So in summary, while gag hoaxes are funny, and I'm not saying don't make gag hoaxes, just make sure they really are really, really funny before you make them ^_^
What you should ESPECIALLY not do is just add dialogue to an existing screenshot. That's not a "hoax", that's a "caption contest entry". You actually do need it to be a situation that can not occur in the game.

[4]when ----- gets -----
Dear God, I've created a monster! Seriously, if you mean to create a hoax series detailing the amusing situations that occur to Sonic characters, make it something new. Boredom is done. We've done it. It's over. We're bored with boredom :P And call it something new. I got a hoax recently entitled "When Everyone Gets Sick Of..." which I think covers this WTGB-name-copying fad perfectly :P

[5]self-insertion

Kulock won't mind if I blanket-quote him here (from the Moogle Cavern Hoax Guidelines): "Even if your character is a green Sonic, with Shadow stripes, and cargo pants, sorry, but you're in a large and unexclusive club there, and hoax viewers aren't really thrilled to see that sort of character." Everything else Ku says on his page is worth listening to, as well, by the way. But yes. Your character's in the game? Great, great. If only we really wanted to know what your avatar looked like. Wanted to know so much, in fact, that we wanted to look again despite the fact that it's already on your button.

More as they're thought of.