Well, don't get too stuck on your RDRAM, or DDR SDRAM, etc...IBM has been working on magneitc memory now for about 30 years...it seems they have not only perfected it, but now have it scaled enough to offer 256MB "sticks".
The cool thing about MRAM -- it doesn't require constant refreshes ala dynamic RAM, it is non-volatile, and really fast.
One of the "predicted" uses is for "instant-on" computers...no more waiting for your system to boot since the entire boot-up and load sequence will simply reside in the non-volitile MRAM. Just turn it in, and POOF, you're in.
IBM is aiming to release MRAM in things such as PDA's, cell-phones, etc by next year with full-scale use in desk-top PC's by 2004.
In addition to that, "desk-top" holographic storage is also a reality. By using a laser to write "data" onto and into a lithium-niobate crystal cube or light sensitive polymer material allows literally terrabytes of data to be stored in a 1 centimeter square cube!
The functionality is way cool, and frankly quite simple. A laser beam is split. One beam passes through a tiny LCD screen (called a "Spacial Light Modulator"). Each pixel of the LCD screen represents one bit of data. The reflected image of this "page" of data is shined onto the crystal. The second beam that was split initally is shined onto the cube at precise right angles. Using "standard" hologram recording principles this way, this "writes" the data onto or into the cube. By aligning the lasers perfectly, the data is literally written in molecule thick layers througout the entire volume of the cube, not just on the surface.
To read the data, a single laser beam is passed through at a precise angle to read a specific page of the data. This reflection is shown onto a tiny CCD which translates the data into bits and sent on its way.
The biggest drawbacks right now are size of the laser, mirrors, CCD, etc, hence the term "desk-top" storage since the device will not fit into a computer case just yet. Also, the more holograms recorded, then the weaker the holograms become. At some point, the reference laser will pick up background interference from other holograms and in effect, you have scrambled data.
Again, IBM is working on this and they have predicted a possible 125GB storage, 40MB per second transfer rate holographic storage device available to the consumer as early as next year.