adopting tools for other needs

EZtoon and Pivot Stickfigure Animator could be used to make storyboards or animatics.

Pixton, Stripgenerator, and Make Beliefs Comix could possibly be used to make storyboards. All of these are online flash tools with click and drag interfaces. Pixton is similar to Pivot Stickfigure Animator in that the characters are puppets with independent parts that can be moved and manipulated. So, if you're not a cartoonist or claim to have no drawing ability this is probably the way to go.

But, really, you don't need to have any drawing skill to do a simple storyboard. Stick figures work for this, as long as it communicates to the animator what you want. That's really all that matters.