Got a dead SSD? My 256GB boot drive packed up yesterday. I tried reformatting it in Apple’s Disk Utility and in the Terminal, and also tried in Windows 7. All efforts to format failed, and eventually the drive refused to mount.
I got this from Crucial Support: plug the power cable into the drive, but not the data cable, leave it for 30 min, unplug for 30 seconds and repeat. After two power cycles the SSD may come back to life – mine did!