A little background info:
-HDD was undetectable despite all efforts on the 16th Feb
-Before that for a month or so it would be detected intermittently by the BIOS - Usually a pulling the SATA cable out and plugging it back in (the 'ledge' allowing the SATA cable's locking mechanism to 'lock' into place broke off, so the connection might have been altered when it is hit accidentally when floor is being cleaned) would solve the problem, otherwise doing the same to the SATA power cable would also resolve the issue
-On the 16th, despite trying in excess of ten times the HDD refused to be detected
-There was a 'tick tick tick TWANG' type of sound coming from the HDD. Spinning the HDD around the axel's axis did nothing.
-An hour long visit to the freezer in a ziplock bag (with air sucked out, of course) managed to get it up and running, so I set it to transfer over files and slept. Next morning I switched off my PC, thinking I could repeat the freezer trick again at worst.
-When I came back, even a two hour trip to the freezer failed. The sound had changed to a "tzzt tzzt tzzt" type of sound.
-Pissed off, I sent it to the freezer for 3 days. Still not working despite my efforts. I was almost resigned to having to redo a lot of work (I keep forgetting to back up) when I read about tapping the HDD on an edge with the force akin to cracking an egg. As I had other more pressing matters to attend to I left the HDD alone yesterday.
-Tapping it on all edges today caused it to whirr like a normal HDD and work like a normal HDD.