We often get computers in where the customer says, "Oh it was just a few drops of water that spilled. Barely anything at all." Of course this could mean that it was swimming in water not that long ago lol. On a serious note, people don't realize just how quickly water can spread through a device. In the case of the laptop in the picture above, water spilled down the back of the device and followed the fan to the motherboard. The damage would not have been so bad had the customer just turned it off when they suspected it had gotten wet. The damaged progressed slowly from corrosion to rust. Just because a machine works for a while doesn't mean it's ok. That liquid will continue to make important components on your board rust over time. So be safe and if you think it got wet, have it checked out.