Two days ago, I found out the hard way that the best way to work digitally is to work locally, meaning, when you're, say, coloring a page, it's best that the page you're working be stored on you're main drive, NOT an external drive.
For years, I stored all my art on a separate, external hard drive, leaving my main drive freed up with more scratch disk space and once I was done with a file, it was already back up on an external drive in case I got a virus or something and had to reformat my computer. Seems like a good plan and that worked out fine for a long time, BUT, turns out it's not the best way to do things. Long story short, I worked several hours coloring up a splash page for Hack Slash #2 and LOST it while I was saving the final version. It was not recoverable, the file somehow got scrambled and I was left with an unopenable PSD file. I sat for hours trying to get it to open, but nothing worked and now I'm sitting her recoloring a whole page from scratch, argh!
So, lesson learned, I now work from my main drive, and when I'm done with an entire issue, copy that over to the external drive and delete it from my main drive. I also find, even though my external drive is firewire and plenty fast, that load times and saves are a bit quicker when working from my main drive, so, bonus!
****LOST SPOILER****
P.S. I attended Jay and Jack's LOST finale party and watched the series end with 2000 fans at the Orpheum in downtown Los Angeles. I managed to make it all the way to the end without shedding a tear, but when Vincent laid down next to Jack, I lost it... sigh.