Hitachi have successfully scaled-down a key component in the hard drive down to nano-scale and this accomplishment allows for a 1 TB Laptop Hard Drive to be created. This breakthrough will allow hard drive capacities to quadruple in the next 4 years. For a desktop you can expect a hard drive to have a 4 Terabyte capacity with laptops and iPod's having 1 Terabyte of storage. To give you an idea of what a Terabyte of information can store it would be equal to 1 million books, 250 hours of HD video or 250000 tunes. Quadruple that for the desktop sized hard drives and there you have an even more insane amount of storage space.
I can understand the need of such storage amounts in a business situation, but for personal use... I have barely broken the 20Gb mark and I bet half of that is just junk anyway. It is still an impressive accomplishment and although not needed right now, a 1 TB Laptop Hard Drive could well be needed in 4 years time when higher res photos will be stored, HD DVD's will be stored and a lot more.
To accomplish this....
Hitachi said it has created the world's smallest disk drive heads in the 30-nanometre to 50-nanometre range, or about 2,000 times smaller than the width of an average human hair.