A few months ago I spilt coffee on my old (2008-09) MacBook Pro. The machine worked OK, but the keyboard didn't respond for some keys, so I used an external keyboard and mouse on the thing.
A while ago I ordered a new top case off eBay, and I swapped it over the last couple of days. Works fine (except the keyboard backlight, but I can deal with that).
I'm happy, especially as most people I spoke to suggested I just replace it.