Your phone might take a dive, but that doesn't necessarily mean it's dead
Rob Griffiths (@rgriff) posted a story to Macworld early this morning describing the dip his phone took in a 10-foot-deep lake last weekend — and how he brought it back from the dead.
His method was pretty extreme (he eventually completely disassembled the phone, dried everything with compressed air and reassembled it), but it's good to know some simpler ways to salvage a phone that's taken a dunk.
First of all: Act quickly. Get your phone out of the wet as soon as you can. Resist the urge to start pressing buttons. Instead, immediately power it down and disconnect anything and everything that can be disconnected. Remove the battery (if your phone has a removable battery), take out the SIM card and open every socket and door that might be covered. Only after that, take a towel and dry the outside of your phone.
A plastic bag of uncooked rice will absorb moisture over time. If you have any of those little packets of "DO NOT EAT" dessicant that come with new electronics, those will help speed the process. Wrap your phone loosely in a paper towel and bury it in the rice. Forget about touching it for at least eight hours. Some folks recommend 24 to 36 hours. The longer you leave it to dry, the better your chance of success. Spend your time using something other than your phone to browse through stuff like this on Amazon.
You might be tempted to use your hair dryer. Don't. Blowing air into your phone is a great way to force moisture deeper into its sensitive innards — not to mention the hazards of excess heat. For the same reason, don't try to dry your phone by drying it in the sun.
There's no guarantee any of these tricks will work. And keep in mind your chances will be better or worse depending on where your phone took its dip. (Fresh pool water is much more phone-friendly than the salty gulf or bay. In fact, I've heard about folks who saved their phone from a saltwater dunking by first rinsing it thoroughly in a swimming pool.)