It's a miracle!
They took it apart, left it to dry over the weekend, cleaned it with magic elf elixir, left it to dry some more, put it back together, tried to boot it up and were - they told me themselves - quite frankly shocked when it did!
After cloning my hard-drive they ran it through some memory tests and stress tests which it passed!
There is evidence of corrosion and yes I've probably shortened its life* but it's working just fine at the moment.
I don't know what I did to deserve this reprieve but I do know I am going to be a hell of a lot more careful about where I put things :-/
So in summary: Yay!
*I'm sorry, baby, I'm soooo sorry! :-(