Praise Pismo surviving Aqua Alta
In my experience the only solution to get rid of the condensation WITHOUT RESIDUAL TRACES ON THE SCREEN is to open the PB (=open the screen) while switched off (battery detached) and to lay it backwards on a heater. 2 important things to remember:
1. do not lay any plastic or otherwise deformable parts of the PB directly on the metal surface of the heater - put something between like a thin cloth
2. do not turn on the heat too much. On a scale between 0 (off) and 10 (max) I suggest 7 or 8.
You might want to know how come I am so sure about all this: well it happened to me at least half a dozen times. I am used to taking my PB (a Pismo upgraded to G4 by Daytech) in all parts of the world while shooting (films) so accidents and incidents are pretty much routine. The PB is now 6 years old, still with it's first upper casing, I changed the lower casing (the one around the trackpad) about a year ago because the thin plastic joint below the mouse button broke and because of too many scratches on the surface.
Liquid in the machine: it happened to me with Water, sparkling and not sparkling, coffee (that was a hard one, had to detach the entire machine, "wash it" with window cleaner spray and only then "dry" it), CocaCola (same routine as with the coffee though it was trickier because I drink my coffee without sugar, whereas Coke is practically liquid sugar with color) and Milk. I guess the most dangerous of all was the Coke incident (my assistant tosses a can of coke and it spilled all over his Dell and my Mac, BTW the Dell died whereas my Mac is still alive as I am writing on it right now), I had read a lot about it's corrosive abilities and was worried about not beeing in time before it destroyed other things.
To finish: I think Apple never ever built a PB as good a the Pismo again; some rumours say the next PB generation is supposed to be pretty similar to it. It better is: the best decision I made a year ago was to upgrade it to a G4. It was worth everyone of the 350$: today I am running Tiger and the machine is even faster as it was with Panther 10.3.9.