Get ready. 3TB hard drives are about to hit the mainstream. Yeah, we can't believe our eyes either. It wasn't so long ago when 1TB was the holy grail of hard drive space, but we guess that's just the speed of technology innovation these days. Now, how much junk you can squeeze into a single 3TB drive? We crunch the numbers... the results may surprise you!
Here's a general breakdown of how much stuff you can cram into a 3TB hard drive. Think of it as mathematical porn for all you media junkies out there.
For the casual consumer:
Pictures - 1-2MB/pic (point and shoot cameras) = ~2,500,000 photos
Music - 4-5MB/song (iTunes) = ~600,000 songs
Movies - 650-700MB/movie (DivX/Mp4/480p) = ~4,500 movies
For the prosumer:
Pictures - 4-5MB/pic (dSLR cameras) = ~600,000 photos
Music - 8-10MB/song (Flac, loss-less) = ~300,000 songs
Movies - 4.7-8GB/movie (720p-1080p MKV) = ~820 movies
We can see the high-definition movies eating up a substantial amount of hard drive space eventually, but really? 820 movies? We don't even think we know of that many movie titles in existence (or worth knowing at least), let alone have the time to watch it all!
Perhaps we should just look at it as if we're overstocking on canned soups for an unexpected disaster. With all of the chaos in the world of Internet today, one can never have too much storage right?

White Enamel Flatwa...
I would think having multiple 1TB HD is better then having "all your eggs in one basket" like a 3TB HD. If that big guy crash it will so expensive to retrieve all the files! Any thoughts on that??
@minimalist1750 Just use a program like RStudio. It works extremely well. On the preventative side make sure that you're constantly checking the health of your drive through the S.M.A.R.T capabilities.
You can never have too much hard drive space.
It's important to note that hard drives are used for a combination of file types. I'm a filmmaker and a photographer. Making a few films and shooting photos in RAW (14MB per photo) quickly eats up space.
That being said, I'd rather have something like the G drives that let you swap hard drives (like a really big floppy) 3TB in one drive seems really risky.
820 movies really isn't THAT many, if you're a cinephile. Even if you start from the beginning of sound movies, you'd just have about 10 movies per year up to the present...
Of you'd start that early with your movies collection, you wouldn't be stuck with 'just' 820 movies. Chances, that a movie that is older than just a very view years is actually HD are very low. So - considering a mix - you'd fit at least 4.000 movies onto a 3TB drive. Which is about 6.000 hours of video? That's more than two years of video if you spend 8 hours watching every single day. Even for a cinephile or an unemployed pretty much, I guess. :)
Okay, 4000 *is* a lot--I'll admit that much!
What about television? A single season can be up to 10 gigs and that's not even HD. For those worried about losing data RAID is really the only way to go.
Massive hard drives are exactly like closets and movie hogs like me get weak in the knees at the prospect of bigger and bigger drives. I'm almost at capacity with three 1TB drives now, although I've recently decided it makes more sense to let Netflix maintain my movie collection than it does to keep buying hard drives.
Still, I'll probably buy another pair of drives soon, one for back up, of course, but since I'm cutting back on hoarding, it'll be a pair of 1TB drives.
And that, as they say, should be that.
(famous last words)
Ripped blu-ray movies takes up most of my space. 8-20GB per movie. A few TB-s gone allready!