Had a similiar incident, though definitely less severe.
Stuck it in a bag of rice, buried it 6 feet underground firmly in a pot of rice (uncooked). Thereafter 48 hrs, took it out, keep it shrink wrapped in tight air tight plastic with little cases of silica gel packs.
Managed to work after 2.5 days. But battery life does seem affected, as an estimate, say could only use to 80% of previous battery life spans. My guess is some of the metal was corroded and just simply cldnt charge that well no more.
Read in some forums that this guy left his nano ON an electrical plug (which can get rather hot). worked for him. Came across some websites that said to fry ur ipod in the microwave. Thought u'ld wana head down that highway of destruction.
In the last case scenario, go buy a very small screw driver, fine brush and white acrylic paint (ah hem). Slightly unethical though.