SanDisk has built itself a decent reputation in the SSD game, and a cheap cache-only drive is a logical addition to its line. Unlike regular SSD or hybrid upgrades, you don't have to transfer your system to the new drive -- the 2.5-inch, 32GB add-on simply hooks up to a spare SATA III port alongside your spinning storage and then you run SanDisk's ExpressCache software to do the rest. The program, which is
