I've searched high and low for something to get me on the right track, it's making me think it might not be possible.

Basically, I want to create a cheap SSD using Arduino (or another microcontroller if it is too weak). I know I would have to implement the SATA protocol on the device and an OS driver for the disk drive. Assuming I could jump those two hurdles, what else would bar me from implementing a rudimentary SSD? I'm not even talking about full production quality, just a SATA wire coming from a mother board plugged into a socket on a breadboard. Do I need flash storage or would I need another kind of chip to handle the data needs?