Hmm... when leaglebob said "external hds" that got me thinking. What do you guys think the life of a Ram-Drive (i.e., pen-drive) is? That seems to be the best storage for data; though the day before mass pendrive storage becomes cheap is probably far away. Granted, you can get 1gb for around $70 now, that's far off from $.70 for 4.37gb.
Oh, and leaglebob, remember the key isn't backing up your data every few years onto the "next generation" of media (in this case, blue-ray). The key is to back up your media every few years onto the next generation of "reliable" media; meaning, if you were converting from cdr to dvdr, you wouldn't want to convert your data on kodak cdrs to optodisc dvdrs