The other night, I had a few. I decided I needed another preset and that I would derive this new preset from my precious. So I poke at the buttons to copy the preset. Without so much as an are you sure, I copied the shitty preset I wanted to overwrite on top of my precious. Now I have two shitty presets and my precious is gone. Crack the manual, look in the index for Undo. Futility in action.
Of course, because I'm a typical lazy-ass, I never actually used the supplied patch librarian software. So it's gone. Gone. Gone. Sucks. Sucks. Sucks.
So today's lesson in the rock and roll school of hard knocks is make sure you have a backup. That may take different forms for different kinds of gear but when you need to get back something you created months ago you'll be thankful.
[Edit: minor typos]
Brain crapped by MMI on 1/27/2011