Jason at 2008-12-14 20:26:00:
Hey-
Just discovered your blog on Scribomatic.
I don't think it's possible to start with "plot," because you can't have a plot without a character wanting something. You might be able to come up with a cool premise, or hook, or setting, but until you have a protagonist, you don't have any sort of story.
The character's desires will ultimately determine where the plot goes, even if external events cause things to happen for the character.
That's one of the big reasons we fall in love with specific actors, no?