Script Summary: Hides the right hand sidebar in the message view in Gmail for an extra-wide widescreen view.
I love Gmail's new 3-pane widescreen view but the message pane always seemed extremely cramped. The right-hand sidebar would eat away precious real estate without adding anything of value for me (I already knew who was part of the conversation, I didn't need to see a summary!).
This script hides that right-hand sidebar, allowing your email to expand to take up the entire width of the 3rd panel for an extra-wide widescreen view!