RPG RPG writing: HELP!!!!!!

[Mr. Maul]

Have you ever been trying to come up with the ultimate RPG?
Of course you have! Everyone has. And when you get an idea for one you always get in a jam? A mental block?
YES!!!!!!

Well, this happens to me a lot, and it probably happens to you. If you've ever caught yourself between a rock and a hard spot, tell your story here. Or, if you know any good web sites that have great explainations of how to create your own RPG, I'd like to know.