as concisely as i can explain it.... two months ago i spilled coffee into my 2nd gen macbook (lower right side of keyboard). i immediately cut power off, drained it best i could and bathed it in 10lbs of rice. was able to restore power by the end of the day. took it to a genius the following day who was able to restore it fully but told me the tech spotted corrosion around the connection to the HDD and that my best option was to consider it on its last legs and try to replace it asap so that i could pull whatever i could off the HDD and transfer to a new macbook. he was right. even though everything seemed to be fine (computer showed no signs of damage), 48 hours after the geniuses diagnosed it, the macbook shut off. now, every single time i try to boot, i hear just one click (HDD ?) and the blinking question mark folder. nothing more so, am i dealing with a HDD failure and if so, can i temporarily replace it with a working spare that i have lying around even if there is mild corrosion at the connection points? or will the corrosion ruin any/all chance of a clean, non-damaged HDD working on the macbook? i know that i will still have to replace this laptop, but i wanted the option of a last resort back-up, rather than a $1,000 paperweight.