I-RAM

gigabyte invented a new device and called it i-ram i think in their site they explain that better than me http://www.cluboverclocker.com/reviews/hard_drives/RAM_Drive/Gigabyte/I-RAM/index.htm
but if u dont want to visit it thats small words about it
Looking for a small, yet extremely fast internal data storage device? If so, then Gigabyte may have just the solution you've been looking for. It's called the i-RAM and it's the latest thing in RAM drives! With the ability to hold up to 4gb in data using up to 4 sticks of standard DDR memory, the i-RAM plugs into a standard PCI slot and uses a Serial ATA interface to transfer data. But wait just a minute...how does the i-RAM overcome random access memory that dumps whatever is stored on it when the machine is powered down? With a battery backup of course! Let's take a look at Gigabyte's new drive technology and see if it's worth our hard earned money.
Specs

Through Gigabyte's custom intelligent controller, i-RAM acts like a regular SATA hard drive at theoretically 1.5Gb/s data transfer rate. By utilizing conventional DDR memory modules, i-RAM is outfitted with four 184-pin DIMM slots that will accept any DDR DIMM and support up to 4GB unbuffered / non-ECC memory. Most of all, the major issue of data lost after powering down is solved by i-RAM's backup battery which is charged by your system on the fly. Without mechanical elements of traditional hard disks, i-RAM's stunning performance coming from the nature of DRAM as storage medium benefits in massive storage access application such as video / audio capture & editing and 3D graphics design applications. i-RAM is the fastest storage device you have ever imagined!