My evac plan involves knowing how to pull my hard drives and having a padded watertight case to put 'em in. (I have three with a total of 400 GB though I'm not anywhere near using all of that) I can always plug 'em into a new 'puter if only to suck the important stuff off of 'em.
Yeah, if we had time, I'd pull the hard drives. But in case of a house-on-fire type situation, it'd be nice to be able to have digital copies of important docs handy.