You don’t need that old SuperDrive, do you? Just pop it out of your MB or MBP and pop in this OptiBay hard drive for unibody laptops. You can use the system as a pair of separate drives or as a RAID drive. The upgrade uses SATA and comes in 250GB, 320GB, and 500GB versions.

The drive is available at MCETech and starts at about $189.

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Add a second drive to your MacBook/MBP