The almighty gerbils are always able to help, even when it seems all hope is lost.
I was having a problem with my macbook air, where waking up the computer approx. 20-30 seconds after letting it idle to sleep causes a black screen with a cursor to appear. The problem occurs regularly, and I have already had the apple store take a look at my computer twice. They have reinstalled the OS, and they even shipped it to an "engineering center" where they replaced a hard drive, some I/O cables, and reformatted the computer again. I have posted a video on my youtube account, with the link below. Any further ideas/sympathy would be appreciated, as it seems that even apple is having trouble with this one.
Link to a video of the problem: https://www.youtube.com/watch?v=4wEbYcAK6sk&feature=youtu.be
i5 3570K | ASRock Z77 Pro4 | 12GB | HD7850 | 120GB Corsair Force 3 | 2x WD Caviar Black 640 GB | 3x U2412M | P182