In case you needed any extra warning, do not leave your iPhone 3G in the rain. It's not waterproof. According to routine testing by the Fédération Romande des Consommateurs:
After a few minutes in the rain the device showed a whole array of technical problems: The battery drained rapidly, the iPhone overheated, the touchscreen and the speakers malfunktioned. And that's not all: even when the cellphone was dry again the problems persisted.
I know what you're thinking—of course leaving an iPhone to get soaked will ruin it. But apparently only two smartphones have failed the rain test, the Nokia N95 and the iPhone 3G. The FRC believes that the culprit is the iPhone's new plastic case. We believe the culprit is the idiot who left his phone in the rain. [20min]