This has happened twice. Once the computer went to sleep while I was working. I thought I hit a key command to force it to sleep but who knows. I clicked the mouse and it came back on. Today while I was writing something, on paper, the computer went to sleep. I clicked the mouse, it came on and went to sleep, I click the mouse the same thing happened, and it did it once more. I finally hit the power butten instead of the mouse on the fourth time and it came on and stayed on. I contacted Apple and they said I could bring it in for testing/repairs. Anyone heard or had this problem. I went to preferences and set it to where it will never sleep. I am too busy to have it checked so I am going to see how it performs in the future. C.