The fastest storage devive is

[Guest]

The fastest storage divice is

 

[DustinM]

If you wanna be literal, then it's the ioXtreme Pro
http://www.fusionio.com/products/ioxtreme/

But if you wanna be realistic, then.
Solid State Drives
After that I think it would be Ram-disks...
But then again some RAM SSDs are incredibly fast...

http://www.storagesearch.com/ssd-fastest.html

Here browse that.

I guess it would partially depends on how you hook up the device to your system.

Excluding the PCI-E bus, cause that there is fast...

 

[MRFS]

Ramdisks, hands down:

See also:

http://www.supremelaw.org/systems/superspeed/RamDiskPlus.Review.htm

http://www.superspeed.com/desktop/ramdisk.php


MRFS