Symbols allow some elegant solutions to everyday problems.
More and more people tend to do storyboarding digitally and, of course, there are professional programs targeting professional board artists.
Here is a storyboard template I designed in Flash for everyone who doesn't mind using Flash's drawing tools.
It is structured in a way that you can draw your panels inside a panel container, using the onion skinning and layers, very much like as if you are working on a traditional lightbox.
These panels automatically appear in pages that have A4 proportion and can be exported for 300dpi prints.
Then the storyboard can be converted to animatic in (literally) 5 clicks!
All instructions are inside the FLA file. If that sounds interesting, give it a go.