Most electronic components aren't harmed by water (I can't think of any that are), so you can always soak it in a bathtub, and then dry it. Then, if your oven goes low enough, set it to 150 and bake it for an hour or two to dry it out.
Generally, it's not the water that causes the problem. Usually it's something like:
- The water contains impurities that leave a conductive path between nodes,
- chemicals corrode contacts, or worse
- chemicals completely dissolve component leads, PCB traces, ...
Note: if there's still water and/or conductive things left on the board, you can destroy the item by powering it up. So if you have an accident, turn off the item immediately, remove the circuit board and clean the circuit board (dishwasher, bathtub, etc.). I've successfully recovered many items with this technique, including a computer that was in an apartment fire (heavy smoke contamination inside the computer and *lots* of water in it. I quickly cleaned it (so corrosion wouldn't take hold) and it fired right up after drying and reassembly.