Hi everyone, I have a late 2011 17 inch Macbook Pro 2.4ghz i7 with 16gb ram, 128gb Crucial M4 SSD, and a Seagate 750gb Harddrive in the optibay. It has been running great since I bought it in December. Last night I realized that the SSD is only showing 68.7gb remaining. I don't keep anything but applications on the SSD. Everything else goes on the optibay so I should have much more space. 'Home' or whatever you want to call it is showing that I am using 22.9gb but when you command + i on the individual folders and add up the space it is only using up 3.5gb. Where is the remaining 18.5gb? The trash is empty, I have used disk utility, clean my mac, etc. I did a clean install on the SSD when I installed it. Trim support is off. If you could help it would be greatly appreciated.