I have used UniBeast to create an installer on a 16 GB USB drive. After having troubles with the install on my PC, I ran UniBeast again, with the USB drive plugged in again. It then said "No Disk Available To Install On", even though not only the USB drive had still 7.24 GB free, but it kept saying the same even after I formatted another drive that had 250 GB free and was also connected via USB (it's no memory stick, but the error msg doesn't require this, and I've been installing systems from a hard disk before on the same PC, so why should that be a problem here, now?) - Anyway, the actual memory stick does have more than 7 GB free, so, the error message is misleading either way. I still have not figured out what its problem is. It worked before, so why doesn't it now, suddenly? I have not even rebooted that Mac since the first installer creation. The UniBeast FAQ does not mention this issue, either. Update: After erasing the OSX installer partition on the USB stick, UniBeast is happy. So either it wants an empty disk or it actually wants to see more than 7 GB free on it. Either way, this should be addressed with a corrected error msg. Also, since it did not accept my USB hard drive with 250 GB free space, the error message should also be clearer about what type of disk it expects (i.e. USB flash drive, probably). However - why doesn't it let me install on a hard drive? I've successfully put other installers, including Windows, on such drives and could install just fine from them. Why, do you ask? Because the drive is much faster, both for putting the installer onto the disk with UniBeast, and installing from it. (If you've been spending two days like me trying to get first Win7, then OSX, on the same PC, you're going to appreciate every minute saved ) Cheers!