They last a lot longer than the tape-based storage of yesteryear, but optical discs, particularly the type you burn at home, aren't guaranteed to survive even a decade. So if you want to pass on that wedding video/vacation photos/copy of Caddyshack to your great-great grand kids, you'll want to opt for Millenniata's new 25GB Blu-ray compatible M-DISCs which are guaranteed to last at least 1,000 years.
The M-DISCs—which burn data onto a more permanent layer made of metals and metalloids instead of organic light-sensitive dyes—have existed as standard DVDs for a few years now. But that provides just a paltry 4.7GB of storage capacity. The new Blu-ray version of course boosts that to 25GB, and although the discs need to be created on an M-DISC compatible burner (many are these days) they can still be played back on a regular Blu-ray player. So it's got that goin' for it, which is nice.
Available in August there's no pricing info on the Blu-ray version of the M-DISCs just yet, but a 10-pack of the DVD versions are about $30, and you can expect the higher capacity versions to be a bit more expensive. But when you break down the per year cost in terms of survival, this is the deal of the century—err millennium. [Millenniata via SlashGear]