→ Bootable Mountain Lion USB Key

UPDATE: Some users have reported getting a “Could not restore – Invalid argument” error at the end of the restore process. Our testing shows the error message can be safely be ignored; the drive can be mounted and will boot your system to install Mountain Lion. As noted in the comments, however, mounting the InstallESD.dmg file before performing the restore process avoids triggering the error message.

Knowing that would have saved me the last hour of my life.