VersionPress

I wish I had a chance to try this one out, but from everything I see this can be essential for many workflows.

Many times you can sit around pointing the finger (especially in WordPress), but with this you can clearly track down root causes and avoid future failures.

Not only does this keep a nice log of everything, but adds a nice UI so that even the one guy being taught how to run with WordPress can track down and revert mistakes!

Download the open source plugin and dive in today or else get hosted with version press (free development sites, probably worth taking advantage of!)