I have a 2011 15" MBP, with a Vertex 240 GB in the primary HD slot, and the original 750 GB HD moved to a Data Doubler in the optical drive slot. I installed only the system and apps on the SSD, and then pointed the system to the User folder on the HD. Since upgrading, I have noticed the battery life is somewhat shorter. I am curious if I can convince my HD, which likely uses most of the battery life, to spin down more often and more quickly, but have been unable to figure out how to do so. There are several facets to this: 1. Can I set the HD in the optical drive bay to preferentially go to sleep more quickly? I am unsure if the Energy Saver options in System Preferences affect both drives or just one. 2. Should I move my most frequent document files to the SSD to decrease the frequency with which I call upon my HD? I have plenty of open space if I don't move Movies and other large files (which I don't use that often in my daily work). 3. Are there any other files I should move from the HD to the SSD, such as Library, to decrease the usage of the HD? 4. Would moving data to the SSD (rather than just system and apps) affect my backups in any way? I ask this because right now I could just reinstall the system and apps on the SSD should there be some corruption. I realize this might be a minor concern, as I have backups both to TM on an external drive and an online backup setup. Thanks for any experienced expert input. I am hopeful this discussion will help a lot of people who are doing the same sort of thing. Its pretty cool to have a lightning-quick SSD, and also have almost a Gigabyte of storage on a laptop, isn't it? Cheers!